I use a 105 F2.5 P, on my 30D , with no mirror problems, maybe the 5D could be a problem.

As everyone said, it should clear. If you are looking for a lens to shoot brick walls, there are many better. If you are looking for a lens to shoot people on a background that is smooth but still easily identifiable, there are lenses with a different look but not necessarily better. If you are looking for a totally blown out background, there are better options.

There is one kicking around my extended family and I can't quite figure out who has it right now, but I want it back! The F3 misses it.

loudtiger wrote:
how does the 2.5 compare to the f/2 AF-D for portraiture?

Here's a shot with my pre-AI 105/2.5 Nikkor P taken with a 30D...considering the extreme backlighting it did quite well...