I'll play down to 5/10 rather than play at a bad table. I also try to find the most passive tables I can. A 30/14/.4 is easier to deal with than a 30/14/1.5 as his bets are easier to interpret.

If I can find a table with a couple of these mouse types, a couple 40VPIP types and a semi-LAG, I'm good.

Generally I go by table VPIP, but weigh in post flop aggression before sitting down.