In conventional commercial hoods, the baffles are intended to collect grease particles larger than a certain size, which they do imperfectly. (Grease particles are distributed over a range of sizes.) It is hoped that the rest of the particles make it outdoors with a minimal amount condensing on the duct surfaces. This process is also imperfect, which is why commercial systems have to be regularly inspected and cleaned as required. Residential operation of similar (looking) hoods is sort of like slow motion commercial operation. It might take a year to generate the effluent that a commercial hood passes in a day. Nevertheless, when one is generating smoke, grease, or other effluent, one wants it somewhere other than on the walls, towels, bedding, etc. A recirculating hood, unless extraordinarily designed, cannot filter adequately to approach the results obtained from system that exhausts outside. Recirculating hoods usually are too small to have aggressive filtration to contain the range of grease particle sizes that would be passed by baffles. I suspect that for such hoods a mesh filter will be more effective than baffles, if the mesh is fine enough. Of course, it has to be cleaned regularly. The finer the mesh, the more regularly one has to clean it, but the more effective it will be. It will also induce a lot of pressure loss that will reduce the actual cfm flowed, but collection of effluent is more important than rated cfm. kas

An air purifier that could handle the cooking effluent would have to filter hundreds of CFM. It would be at least as large as the VaH recirculating hood, but by not being over the cooking zone would be less effective in removing grease before it settled on the ceiling, walls, and furniture. There are commercial systems for wall ovens called "eyebrow" hoods, but I am not aware of any advertised for residential use. In any case, even these will have trouble dealing with the blast of effluent when the oven door is opened. You can try for partial capture and containment at the ceiling level with a separate register and blower system. (Note that this would call for additional make-up air over whatever level is needed for an externally venting hood.) Otherwise, you would have to consider commercial perforated ceiling systems. An example is here: http://www.kitchen-ventilation.co.uk/heydal

I haven't searched for one, but it is possible that Broan/Best has a recirculating system with both grease filtering and charcoal-based odor filtering. To the question: Generally baffle filters are superior in grease extraction efficiency. This is why commercial hoods use baffles. Specifically, the baffles remove the larger end of the particle size spectrum while retaining their performance no matter how much grease is collected. The smaller end of the spectrum is expected to (hoped to) exit the system on the roof. The pressure loss of the baffles remains the same, greasy or not, and this allows the overall air flow to remain constant. However, baffles work by centrifugal extraction due to the air making two reversal in the baffle space. This requires some minimal velocity that likely depends on the details of the baffle design. For modest cooking where low blower speeds are adequate, there is a point where mesh filters -- if kept clean -- may become superior grease collectors. Mesh filters work by impingement. A hybrid baffle system seems to be intended to filter by mesh while providing the appearance of a baffle system. In some commercial applications, the stringent filtering requirements lead to stacked filters, the first usually being baffles, followed by mesh, ball bearing, and other schemes that address different parts of the particle spectrum. UV disassociation of grease and odor molecules is also popular.

@athleticannie - the hoods you are picturing are exorbitantly expensive. If you can afford those, you should be able to afford running a duct to the outside. You've been mysterious about why you must have a recirculating hood. The level of elaborate hood you want is almost never used for a recirculating hood due to the cost of such a hood for what is essentially an ineffective exhaust. The reason it is called a "recirculating" hood is that the effluent will be exhausted from your cooktop, run through a meager charcoal filter, and then circled back into your kitchen. Your smoke alarm will go off for anything smokey like grilling a steak, because a recirculating hood will be circulating the smoke back into the room, the alarm sensor will detect it and go off. And, as others have said, the hoods you pictured are not suitable for 8' ceilings. Start over with rational concepts of what recirculating hoods mean, or, see what can be done to run an 8" or 10" duct to the outside. Here is a link to an excellent company I have worked with that custom makes the hoods in the styles you show. The inserts are sold separately. Peruse the site, and you can get an idea of the costs of what you are talking about: Handcrafted Metal Custom Hoods