What I have found while looking for a women's drysuit is that the "standard" women's sizes offered by the manufacturers are only right for a few women. They do not work well if you are short vertically, but large in any other dimension (i.e., bust, waist, and/or hips.) In looking at the dimensions for each of their sizes, I would ineveitably fall in one category according to my height, and another for my hips/waist and a third according to my chest dimensions. This was true for EVERY manufacturer that I tried. I believe that a similar dilemma applies if you are a tall woman who is somewhat slim.
However, I tend to have a hard time finding stuff that fits me in general, not just for diving. I ended up getting a Large BARE Drysuit (7mm neoprene) and then having the legs and arms shortened after I bought it. I like the BARE suit a lot, and I actually did find a BARE WETsuit off the rack that fit me pretty well without any alterations. If your sizing requirements fall more into a "typical" range of women's sizes, there are probably several brands that might have something that would work for you. Try BARE, O'Neill, DUI and Harvey's to start. You can usually get the dimensions for each of the manufacturers' sizes for women from their respective websites.
In terms of fit, neoprene wetsuits are more strectchy, and can therefore be a little more accommodating if you are close to the boderline between sizes in any of your dimensions. "Bag" suits, on the other hand, are not cut to fit as closely, and allow (require) more layering underneath. In some ways bag suits are more accomodating in terms of sizebecause they are less "form-cut" than the neoprene ones, but you don't want an excessive amount of extra material in any dimension with a bag suit because it will result in a lot of drag.
The best option (for many women) is a custom drysuit, but they are very expensive. I couldn't afford one, and now that I've had my BARE suit altered (which cost me $75-$100, I think) it works very well for me.
One more thing: the boots that come standard on women's drysuits are often too big, at least among the women divers that are in my dive club, so make sure you check what size boots will come on your drysuit. I wear a women's US size 7 shoe, and had to have BARE put an XS boot on my L drysuit when I ordered it. I don't think they charged extra to do that, but I'm not completely certain.
Hope this helps!
otter-cat
