For most terrain, I've never really found free standing to be much of an issue. Most tents aren't truly free standing anyway, almost all require pegs to prevent them from blowing away, let alone attaching the fly. I have come upon a few places where I just couldn't get a peg in, but those places almost always have an abundance of rocks to use as stakeout points. I've been able to use my non free standing tents just about everywhere. They tend to be lighter and easier to set up than comparable 'free standing' tents.