I've been a lifelong fan of the Boston kind, ever since Campbell's came out with it as a condensed soup (then Soup for One, then Chunky, then Select, etc.). It was a step up from cream of potato.

I'd give the best restaurant chowder award to SHELLS (multiple locations in Florida). Not cheap at $6+ a bowl, but very rich and loaded.

They also do a good one at the Paris steakhouse in Anchorage, and I like the one at Legal's (would be embarrassing for them not to have a good one).

Also tried the one at that place in Provincetown on Cape Cod that keeps winning all the awards and found it to be very good.

In the "cheap but still pretty good" category, I would have to say Skipper's product in the Northwest (a fast-food place) isn't half bad, and you can get on an all-you-can-eat basis with some meals.