Joe
it's all personal preference.......I shoot a 48 inch recurve most of the recurves that are on store shelves are 60 inch that seems to be the most popular........I started with a 60 but changed to a 48 mainly because I just like a shorter bow.....the 48 is a little harder to shoot but once you get used to it it is great

targetbutt
I don't know about what you mean by the word "pro". If you mean hunting recurves, they're short to make it easier to shoot from stands or just to go through bushes. Imagine trying to do that with a 68" bow, too much of a hassle. For target work though, you do want the longer bows, since you don't need to worry about size. Basically, the longer the bow, it'll be less snappy but more stable. Short bows are snappy but unstable. I personally shoot a 70" bow. Very smooth to draw and give me great contact with my face, I have a rather short nose. Another consideration is stacking. Short bows if not designed properly will stack quicker than a longer bow. For smoothness, if your draw length is 24" and under you need short bows of 64" or under. Draw length between 24"-27" then it's a 66" bow, 27"-30" means 68" bow, and 30" and up 70" bow. That's just a rule of thumb, I know people with 31" draw and shooting 68" bows just fine, another friend with a 30" draw shoots a 60" bow.