Obviously we like tight pussies, but I have to say that my best sex usually isn't with really tight pussies. I definitely love the feeling and ego-trip of stretching a pussy as I enter it, and it can make for a more heightened/exciting sexual experience, but it also has its downsides. 1st, it takes time to get the pussy nice and stretched out so you can fit your cock all the way in. 2nd, that's time you could be fucking away. 3rd, (for me, at least,) the act of stretching out a pussy can sometimes be the best part of the experience; consequently, between the realization of what I'm doing, the amazing feel of a pussy that's too tight for me, and the very arousing responses & gestures that girls make while they have a nice fat cock that they're not used to stretching their nice tight pussies, my arousal level usually spikes. As a result, after all of the work I put in to get into the nice, tight pussy, I don't even get to spend as much time in it because I'm too horny by that point. Sure, I can go back in for another round, but that leads to my 4th downside: if a girl is tight enough to warrant stretching on your way in, she's probably not used to your girth. Every time I've fucked someone (either new, or just someone I haven't fucked in a long time) that I have to stretch out, they usually end up getting sore-- and that inevitably happens before I'd like them to be throwing up their white flag at my cock. The way I see it (based on experience), I've only got so much time-- under preferred conditions --with a girl's pussy before they throw out their white flag; girls that I haven't "broken in" do that much sooner than otherwise. I'm sure other guys can attest to how frustrating/disappointing it is when you're just getting warmed up and the girl says she can't take anymore.
So, if I had to chose, I'd chose a tight girl who you could have a few times, enough to break her in and get her used to your size.