The 2.5 is a great lens, its small, has very nice bokeh and is quite sharp. I prefer the EF 100/2 USM or 105/1.8 AIS over it though. On a 5D really the 100/2 is a much better choice. The 105/2DC is nice, just amazingly sharp, but it doesn't focus as far before infinity as either the 105/2.5 or 105/1.8 do.
That 105 f/2.5 is a great lens. The AIS version I have has a built-in hood. I got mine from cogitech at a great price (thanks Paul!). He tried it out on his 5D, but he had too many alt lenses so was making room. Lucky me
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.
