Anecdotally people say that BS simmers but there is no way to compare in the way you can the top end of heat, BTUs to BTUs because they have never said what the BTU rating is on the low end as other manufacturers have done. They rate in temperature which is pretty meaningless. There are work arounds for that though. The high BTUs,with more flame to the center cannot be worked around other than to use something like a cast iron pan instead of a wok. Only you can decide if it is worth it to give up that function for $2000. You might also buy the package and sell the Miele rangetop and buy the BS.

Search Wolf blue chipping on this forum. This has been a long term problem and no fix.

I have a BlueStar 36" (range not top), and it's incredible for stir fry, vastly exceeding the other two options. I've never had trouble with chocolate or anything else really, that needs a gentle cook. Though chocolate I always do in a double boiler so it's hard to get wrong. Have you considered Capital? It might be a good fit based on what you've said.

I am a huge Miele fan, but you may want to read the reviews of the range here. The best reviews are lukewarm.

Here is the long thread http://ths.gardenweb.com/discussions/2812367/new-miele-dual-fuel-gas-range-experience.

There was a poster on the kitchen forum who go the range as well- I cannot remember her name- I loved her kitchen very much- at any rate- she said the range was fine- but definitely what she would expect for the money.

I hope this helps. I realize there is a lot to sort through.