All Wynn NL games are uncapped. The 1/3 uses $3 chips, and runs on a few tables 24/7.
TI has a 1/3 with a $500 max, usually on on or two tables.
Most rooms have a $200 max, but Ballys/Harrahs/Paris all have a $300 max. Caesars has a $500 max.
Complete listings at
www.allvegaspoker.com (see the limit charts).
Worst players are generally found at the center Strip properties like Ballys/Paris/Flamingo/Harrahs. Excal has bad players as well, but I don't like the $200 max there.
In general, all 1/2NL in Vegas, anywhere, will have bad players. Its the bottom of the barrel NL game, so it will always have the worst available.