I wouldn't recommend SVN any more (it had it's time, but it passed already). I agree that any source control is a great step forward, actually it was something that helped us to move forward to developing bigger apps in my first company. But after some time with SVN you'll hear about distributed source control systems and about everything it can do. And you'll want it (your dev definitely would). So you'll waste time to migrate stuff, and to learn different approach.

So I would recommend to use best SC of available. From all, I'm familiar only with SVN and GIT. And with the former one one can do more.