An observation regarding the 33s

[45suited]

I have just recently started playing the 33s, so this is based on a small sample size. But I have found one thing that really jumps out at me and I'd like to find out if I'm way off base.

When I played the 11s and 22s, one of the most profitable things for me to do was simply bet for value. The players were very loose pre-flop and could not evaluate the strength of their hands post-flop. Simply betting for value and letting them call you down with bottom pair or some crazy backdoor draw (or ace high) would get the job done.

At the 33s, I've noticed a couple changes in the general play. (I've had the benefit of single tabling for a while since I moved up. Just trying to get comfortable.) The pre-flop play seems much more sane. Nobody calling an all in pre-flop in level 1 with QJs or whatever. But here's the striking difference: Playing my good hands from behind, check-raising or check-calling, so far has been a gold mine. It seems like so many of these guys can't resist calling your pre-flop raises (with position) just to make a play on you. (They don't seem to take into account that I haven't played a hand for 3 orbits before making my raise.) So anyway, what I've noticed so far is that the big difference seems to be that against alot of these guys, they just cannot resist the temptation to make a move on you if you show any kind of weakness. Obviously there are coordinated boards where you would not dare do this, but my question is, is this the general trend as you move up in buy-ins? It seems like the money is made on the lowest levels by simply value betting, but so far, I've stacked a bunch of guys simply by checking top pair. I can't believe the absolute garbage that they are pushing when I check. It seems like the players on the 33s are (obviously) generally better than the 11s and 22s, but some of them seem to know just enough to get themselves into a world of trouble if they are playing against people who have even the slightest observational skills.

Maybe my observations are not valid due to sample size. Any opinions on this subject would be welcomed.