This is a fairly common set up and your sales person is correct. A large pot on a smaller element just gives a smaller heating area on the pot. A 10 in pot on a 8 inch burner simply means that 1 inch all the way around the pot will not be getting direct heat. It's not a big deal.

Look at the Bosch Benchmark and 800 units also.

I would consider the Bosch units dan1888 suggests, or Miele. I see no reason to settle. I have a Gagg unit my pots fit the hobs. I am installing a Miele unit in my ski house and I expect the same. Of course if you have great pots the cold outer rim will be mitigated by superior heat transfer, but why?? You are not looking at the bargain basement end of the market. I would want the whole of my pot heated.

The wolf large element is the same as the miele - 11”. The others elements on the wolf are all the same size which I find provide excellent flexibility in pot placement. There is no issue with a 12” pan on the 11” and I use 10” pans all the time on the others. You can bridge all 4 elements together for a huge cooking area if you need to like a very large griddle Or huge pan.

You can also put a 4” pan on any element including the large one - the wolf has excellent pot recognition. I finally did find a pan that the wolf woul not recognize - a really cute 2 1/2” butter melter I picked up in Sweden. I just put it in another pan and set that on the element - works fine for melting butter/chocolate etc.

If you needs several 12” or more pans on the burners at the same time - zoneless would be the best option. Thermador has a new zoneless model available (or soon to be) that can handle up to 6 pans simultaneously.

Thanks everyone!