It all depends on the type of diving you plan on doing, cold/warm, deep, things of that nature. You will most times not even be able to tell the difference in the effort of breathing on a low end and a high reg. I have used a Mares R2 Rebel, which is a low end piston, unbalanced reg, and now have a Zeagle Flathead 6, which is a high end balanced diaphragm reg, and in reality I cant say that the change was worth the $$ aside from the fact that I eventually plan to tryout some tech style diving. Best advise would be to talk to your LDS and fellow divers in your are, try out all the regs you can, then make the decision based off of all of those factors.