If I do go for the Cannondale, I think I'm going to get the small . In all honesty the frame size just seemed to fit me better. I got on and was comfortable immediately. I guess that's the important part.

If I do find that I'm riding a little too upright, I can always flip the seat post, as was recommended or go for a bit of a longer stem.

Thanks all for the replies. You've got a newbie friendly site, with a lot of friendly and helpful members. Thanks again, and please add any more input, it's all been beneficial.