Hi,
I've been a lurker for several months; I finally have something to offer.
Erik, I went through the same search you're going through. I burned
out a KitchenAid on bread dough. Cooks Illustrated recently
explained the mystery of high-wattage mixers that have no power -
ignore the wattage ratings; they don't tell you a thing about how
well a mixer will perform. We found that out the hard way, and went
through six mixers before we finally found the Hobart N-50, which
handles my multi-grain dough (dry ingredients are 50% seeds and whole
grains, 50% flour) without flinching.
I recently bought a spiral dough hook that's sold for the new KA
6-qt; I find it develops the gluten better than the standard 'J' hook
does, though the 'J' hook handles smaller batches of dough better (my
spiral hook is coated - that may be its problem with small batches).
It was expensive (the prices range from $500 - $1600 depending on
age, condition and source), but we wouldn't think of getting rid of it.
There are probably other mixers out there that are as good, but in my
opinion, if you want to make bread in "home-size" batches, this one
will do the job without breaking down.
Caroline Rumsey