This is such a hard decision to make
! Ahhh, tearing my hair out!
, well, I guess I can't go wrong either way really. I already have 2 minolta zooms, 35-105 and 100-200. They're not great in low light (particularly the 100-200), but so far, have been very good to me. My lens lineup would definitely benefit from either the 50, 24-70 or even the 70-200 and I do plan to change entirely to large aperture lenses over time.
Looking at the weaknesses in my kit, I think the weakest link is the 100-200mm or my noise performance. The 100-200 is slow to focus, particularly in low light and I've missed a couple of shots because of it. My 35-105, I couldn't be happier, and I do have my kit lens (18-70) in the off chance it fails, where as I have no cover for the 100-200 (which is a good range for me, especially in a thick crowd where I need to isolate someone, which so far, is a lot of the times).
I am also irritated by noise a little. A part of my product is a printed 12x12" album. So far, the noise (on the computer screen, haven't gotten the album yet, next week maybe) looks fairly obvious since at those sizes, you're basically doing 100% crops. In fact, thats been a big complaint for me. If the pictures are small (say 5" in a layout), then the noise is hardly visible, but since I like to go large, it has been an issue. I just have to see if anyone else will notice it.
So changing the kit a bit:
-A200+Sigma 70-200 (more practical since that's my weakest focal length)
Leaning towards the A700 just for the better noise
(unless, the improvement is far less than I hope - can anyone clarify?
). I would later need to get the 70-200 & the 24-70, probably in Dec. if all goes to plan. Still uncertain though.
*** Edit ***
grahamnp, I see your point, but I need a body for redundancy more than anything else. Taking money from people and not having a backup body is a risk I am really not going to take. Currently I am trying to build up my rep. and portfolio, so I have done a couple of weddings for free and since it is for free, I clearly state that I only have one body, and if it goes south, well .... sorry about that. Even then, I felt really uncomfortable saying it.
*** End Edit ***