houses14, my Imperial range hood is not an insert, rather an under cabinet ss hood. However, the materials used, and the quality of construction, the fan motors, are the same with minor variances to allow for space restrictions within the smaller size of my hood. Construction wise, it is all that I had hoped for, was easy to install, and has functioned beautifully. Packaging and shipping were excellent. The ss is marine grade. This means that the amount of chromium in the ss will prevent rust from forming in the interior of the hood over time. The electrician informed me that their fan motors and switches appeared to be top quality. The warranty for my hood is 7 years, which is almost unheard of in the industry. Their specifications and installation instructions are right on to allow for optimal operation. For example, my duct is 8" from hood to roof jack and had to have a certain rise in height from the hood before the first angle in the duct work. Baffles remove and reinstall easily for cleaning. It was a joy to call Imperial direct with technical questions at their manufacturing headquarters in California. Someone was always immediately available to answer my questions regarding their vent hoods or recommended installation. My installer was promptly referred to their engineer for technical assistance as I requested that the wiring that would automatically turn on my hood once a certain temperature below the hood was reached be disconnected as I did not want that feature. To me, having that level of service available when answers are needed means a great deal. I found that the folks at headquarters were always honest even if it wasn't the answer I wanted and that they knew their stuff. Their light and fan switches are continuously variable which is rare on vent hoods. This means that they both function like a rheostat with a continuous increase, or decrease, rather than clicking up or down discreet notches, such as level 1 to 4. Also, I liked having the option of installing the switches wherever I wanted remotely, rather than being mounted to the underside of the hood. The hood easily handles removal of odors, steam or grease beneath it's surface. I've found that if the hood is allowed to run for about 10 minutes prior to cooking that it can be operated at a lower level and do a good job. The hood on low is fairly quiet but is noisier than I had anticipated at higher levels with having dual fans and baffles. Also, highest cfm level is 1000 which is a factor. However, I used a different size led bulb than Imperial recommended. I now have a gap around the bulb that needs to be filled with a rubber gasket. Also, the temporary roof jack is too large, and the correct one is waiting to be installed so the jury is still out on the noise issue. Noise level was quite an issue for me, but even if it remains unchanged, I would still buy the same hood given how pleased I am with the overall operation and that I can easily live with the noise that I now have. I'll have to look up the name of the online vendor I used and will add that information tonight.

What type of cooking do you do? Lots of grease? Lots of onions and garlic? Lots of deep frying? I've had downdrafts, custom hood with insert, regular over the stove microwave with direct vent to outdoors (outside wall) over a 30" gas stove. The Micro over stove directly vented to outdoors worked great (micro over stove not my favorite). The downdraft JennAir with grill and downdraft worked great. The custom hood with insert was my favorite aesthetically, and vented through the roof and worked fine. I don't fry a lot of foods (less as time goes on), virtually never deep fry, and use lids a lot because I don't think anything keeps the smell of frying onions contained (just my opinion). Downdrafts seems to get a lot of pushback but the one I had was terrific. I think you can have reasonable aesthetics, reasonable cost, and reasonable effectiveness :) though perhaps not great :) But though we cook a lot (if guessing, I'd say more than 85% of the population) and microwave very little, I have never felt the need for super-high power and I don't like lingering odors. If I were doing a new kitchen, I'd do a downdraft because I really lean towards clean lines and more modern interiors. So, the bottom line I think is to consider how you cook, and if you cook lots and lots of greasy and odiferous foods on a daily basis, super high power performance might outweigh anything else.

Where duct equivalence is a requirement, two 8-inch ducts could be used to match a 10-inch duct. In any case, searching this forum should have led to commentaries on determining requirements before picking hoods. Decide how much cooking plume effluent you want to capture by how much the hood overlaps the possible cooking pans and locations. (Assume a 10-degree from vertical plume spread.) Then use the area of the resulting hood to determine needed air flow rate when performing hot cooking (even if it is on only one burner) by multiplying the area in square feet by 90 CFM/sq.ft. Then, for the case of going directly out the wall with free air flow MUA, assume a factor of 1.3 for baffle pressure loss. This will raise the rated CFM needed for the blower by 1.3 such that the rating should be 1.3 x 90 x area in sq. ft. (Note that this is less than the 1.5 I usually suggest for normal duct lengths, less than perfect MUA, and a duct silencer.) If the hood or insert is a VaH without baffles, use 1.1 to compensate for minor losses such as from the outside cap loss and imperfect MUA. Example: 45 ft x 2 ft = 9 sq. ft. Desired flow is 9 x 90 = 810 CFM. Rated flow for conventional baffled hood then should be 720 x 1.3 ~ a nominal 1000 CFM. While equal blowers mounted in the hood or just outside via a minimal duct length will have roughly the same noise, outside mounting may allow a larger blower that one can run at less than full speed. This will greatly reduce blade tip turbulence noise, which otherwise dominates. Abbaka and Wolf and Broan, for three examples, make down-roof radial blowers that should be adequate to mount on a wall. Exterior aesthetic considerations may influence inside vs. outside, but a low pressure loss cap will not be much larger than a motor housing, and you get a damper with the housing.

Unfortunately, @jlarsen321 did not return with a description of the system selected, or its observed performance in the context of the cooking to be performed. If one imagines near-perfect capture and containment from a commercial system, and then attempts to squish this mechanical system into the space available in most residential kitchens, including duct placement limitations, MUA system limitations, etc., one eventually finds that the path of commercial system approximation leads to one of two endings. In the first one spends a lot of funds on the higher air flow hi-end residential system that is almost as good as the commercial system, but it fits and is more aesthetic. In the second one spends lesser funds on a system that may be good enough for one's cooking style, or at least better than no system. A story from the past: Once upon a time (1984) a good friend of mine, a coworker and part-time professor, brought his Chinese student to our house to cook Chinese food on our then coil electric cooktop. This cooktop was part of a cooking center with low ventilation flow rate, but perhaps a tad better than the standard ventilation put into kitchens of the time. When it was all over, we were full of great food and the kitchen surfaces were full of oil, requiring a major cleaning job the next day. That began my quest for better ventilation, initially limited to boosting the flow rate in the duct path. Actual competent ventilation was not achieved until the end of my kitchen renovation starting in 2008. So it is not trading off performance against cost that is bad, it is not knowing what the result will be versus one's goals that is bad. My hope is that review of the many kitchen ventilation threads here will lead the wannabe renovator to a considered solution, if not an out-of-reach ultimate solution.