I work at a summer camp we have about 20 head and our saddles are both leather and Synthetic I use what I can find that will fit, I like the synthetic saddles they do hold up will if you take good care of them they don't hold up will to falls and stuff like that, I have found one saddle that had a broken tree after a horse fell over on it but hay a horse fell on it. The leather saddles need for care as far as oil and such, the synthetic don't seem to "fall apart" like a leather saddle can, leather dries out and breaks the others don't have that problem.
Now all that said, I personally HATE riding in the synthetic saddles I find them to be VERY uncomfortable. I have a very large leather western saddle that I like very much. At the end of the day, I like to think that my saddle could be past down if I take care of it, the synthetic saddle will always just be a saddle. Good luck what ever you end up with a good saddle that fits the horse and is comfortable for you to ride in is an investment take good care of it is should last you for years. (unless you are in showing, then you will need to changes saddles to keep the judges happy. :) )