Don't be too tough on your BS dealer, previous generation RCS ranges did not have convection ovens. My guess on vintage Tappan range would be about 9k-12k btu burners. Generally the cheaper range people are considering is the better value,and this is especially true here. The RCS with convection oven is a really really good value. You always need to pay that extra premium for more performance. But there is a reason there are Dozens of RNB fanatics that post here every week and rarely an RCS owner raving about his range.

What one wants is to have the hood aperture size overlap the rising and expanding effluent plume. Aperture in this case refers to the area at the bottom of the hood that can be expected to actually capture effluent. Generally this is the empty space within the interior sides, but in some cases might include some of the edge (with enough flow rate and/or steep enough angle). So, given an area at the cooktop that represents the contour of the bases of all pans that might be employed on the burners/hobs, draw an imaginary line upward from the contour edge expanding out at, say, 10 degrees, to the height of the hood aperture. (This is equivalent to multiplying the hood height by 0.176 or thereabouts, to find the edge of the preferred minimum overhang of the aperture.) Very high hoods need additional overlap beyond this to resist cross drafts from helping the effluent escape. If wood is exposed at the bottom of the insert enclosure, its distance from the cooking surface must comply with the range manufacturer's minimum allowable distance to combustible surfaces. If Rustic-R-Us is intended (cabinet-wise and flame-wise), then maybe cabinets made of woods that smoulder instead of burn might be considered, such as ipe or redwood. kas

It just seems from what I've read here, there is a lot more trouble with the ovens in American ranges. It seems that the service can be more of a gamble too. If you search American Performer, you can read more. It is the closest in function to the RNB. It has star shaped uncapped burners like the RNB but with a semi sealed burner tray. It might be ok for a range top but I would not want the range. American also has ranges with capped and sealed burners and lower BTUs. Their DF has sealed and capped burners and a fairly simple oven, single fan, with only a standard bake and a true convection mode. There is very little in the manual so I would want to really see how it worked before I bought. If you don't have confidence in a local dealer for BS, consider buying from Trevor Lawson at Eurostoves. He takes excellent care of his customers and has helped some on this forum who did not buy from him.

I see this thread was recently raised from the dead and figured I'll share my $0.02. We remodeled a smallish galley-style kitchen in 2019 including install of a 48" RNB w 12" griddle and matching BS hood. Range was about $10k, hood and makeup air probably another $10k installed. I worked in college as a cook, so I knew I would love the griddle w/thermostat control, and I was right. I heavily debated either 24" griddle or chargrill, but decided to get the 6 burners. I'm happy with my decision but honestly I think I'd be just as happy with one of the other configurations. One thing I definitely don't regret is going RNB instead of Platinum. The 22k burners are plenty hot even for stir fry and deep frying, and the griddle is so good I can't imagine not having it. One other thing... as winter is approaching this year I started thinking about grilling indoors. I was wondering if there is an aftermarket grill grid that would fit above the BS burners similar to the Platinum grill/griddle. After a lot of searching I found Grill Grates, which has a commercial offering that is almost a perfect fit. After a few tests, I can say it works very well; better sear than my outdoor grill, in fact. I can add more details or photos of my setup if you're interested.