This is another generic question with many possible answers, so please forgive me a head of time.

Given it probably depends on film/developer choice, subject matter and "quality" of light, but what is the experience of the group for maximum "reasonable" enlargement for black and white prints for the given formats if using Ilford HP5 and HC110b, or similar combination(s):

6x7
4x5
5x7
8x10
11x14

When I have something worth while printing, I would like to know what I could expect to look great (provided I did my part) at the largest print size for 5x7. Though I can accept grain in an editorial or "street" image, I probably want it minimized in a gorgeous land or cityscape. Portraits could go either way.

In addition, I am contemplating 4x5 or 6x7 for portraits, probably 6x7 for convenience and that it would yeild a 20" print just fine. I am just curious what an 8x10 and 11x14 can do - thinking about Avedon's "In The American West" and Clyde Butcher's current work in the Everglades with I think his 8x10's and 11x14's.

Thanks guys..