These are the lenses I use with my Minolta 7D. I tried quite a few others, zooms just don't cut it in SO MANY ways, and other focal lengths either lost preference or were redundant. I have no holes in my lineup, focal length spacing is very good, and there are a couple specialized lenses (like the macro) that give me diversity. The three primes are top of their class in image quality. Someday when finances permit I will replace the 100-200 with a 200/2.8 prime. No suitable primes are available in the 10-20 range, but I have also found that in this range the Sigma performs extremely well. I will probably keep it until I move to full frame, then buy a Minolta 20/2.8 as a replacement.

Sigma 10-20mm f/4-5.6
Minolta 28mm f/2
Sony 50mm f/1.4
Tamron 90mm f/2.8 Macro
Minolta 100-200mm f/4.5

35mm equivalent: 15-30/43/75/135/150-300 (That 43mm would be a tough one to duplicate in full frame, while pentax makes one they aren't likely to have a full frame body any time soon).