I have decades of experience as a professional chef, restaurant owner, caterer, and baker, and cook at home extensively. I have cooked on every conceivable commercial device, from french flat tops to camp burners. At home, I have owned Thermador, Viking, Capital, and Wolf. Based on all this, I can say that Capital was the absolute worst range I ever cooked on, for a host of reasons, and I would caution anyone against buying a Capital, even though it seems to have a lot of neat features. I presently have a basic all-gas Wolf, 48", with four burners, flat griddle, and BBQ grill, and I really love it. In fact, the grill on it compares favorably with many commercial grills I have used, and is better than many.
I like all-gas because of the faster response, and also because in case of a power outage the ovens will still work drawing only a modest current from our generator. The Wolf does not have as many BTUs as some ranges, but that can be an illusory distinction. For everyday cooking serving 2 - 10 people, it has plenty of output. We use mainly heavy tin-lined copper, and do not lack for heat. I do like having the flat griddle, though, because that is best for heavy duty searing and frying, such as browning meat for stews, sauteeing veggies, or even stir-frying. Both the griddle and the BBQ are powered by infrared sources, which provide great response and nice even heat. There is also an infrared broiler in the oven which works very well, although as with any such broiler it is in an awkward place to use. Certainly good for crostini or the occasional broiled fish, but less convenient for broiling steaks.
About the Capital -- it looks well designed and well made, but ours arrived not functioning and despite struggling with repairs for over a year, the Capital folks never really lived up to their warranty. The ovens were mis-calibrated, and even after calibration burned stuff on the bottom and left it raw on top. The flat griddle would not hold a steady temperature, and died when we put a lot of food on it. It was also very uneven, and you couldn't cook 6 pancakes at one time because those on one side would burn before those on the other started browning. The char grill was OK, but nowhere near as good as that on the Wolf, and another problem was that the grates were loose and tended to fall down when you cleaned them. There were some other annoying things as well -- for example, the grates on the burners did not give good coverage so smaller pans did not balance well, and they had little rubber feet that fell out, so the grates scratched the base surface and rocked slightly. The worst thing was the responsiveness of the warranty department, though. They simply did not seem to care that their stove was not working right! In fact, as we continued to complain, they sent a rep from the regional distributor, but it seemed not so much to figure out how to fix the problem, as to confirm that we actually had a problem. They simply did not take our word for it that flames were coming up out of the back of the griddle. Yet another problem: Capital crams stuff in behind the front control panel so tightly that repairmen had trouble packing it all back in, leaving the panel bowed out.
Incidentally, eventually I had to sue Capital because they could not get the range going, but the dealer stepped in and credited me the full price of the range, so I paid the difference and got the Wolf I now have. Ironically, the Wolf had a small warranty problem too, but the dealer was able to fix that quickly and I have had no further problems. This further confirms that there are some fundamental design flaws with the Capital.
Previously, we had an older Viking, and I don't want to comment on that because it was an old design so I don't know about the new ones. We also had a Thermador about 8 years ago which we really loved also. The griddle on that was the best I have seen, but they have replaced that model because the griddle was steel and could rust (heat response on carbon steel is about three times better than on stainless). Another problem with the Thermador we had, as with all closed burner models, is that the heat comes out sideways from the burner, so the heat tends to spread in a circle (or star with the new Thermadors) with nothing in the middle. That makes cooking with small pans very difficult. Another annoying feature is that the extra-low power on Thermador works extremely well for melting chocolate or keeping things just warm, but it does it by turning the burner on and off, so there is a constant clicking of the ignitors. However, the functionality was excellent.
Hope this helps people considering new purchases.