The big difference between big-bet (Pot-Limit or No-Limit) Omaha Hi/Lo and Limit Omaha Hi/Lo at partypoker is that the former plays much more like Omaha High. Low hands become much less valuable because of how often they get quartered.
If you get quartered in Limit games at partypoker, you may not lose too much of your overall chip stack because the action is capped on every street. In Pot-Limit games at partypoker, however, getting quartered can be much more expensive because you may have had to call big bets on both the turn and river before the hand ended. Losing half your stack in this situation could be your best-case scenario – and getting completely felted if your hand is counterfeited on the river is a real possibility.
Because the high end of the pot is often more valuable in big-bet games at partypoker, I recommend looking for hands that play well both ways or for hands like J-J-T-9 that just play high. Hands that are going to scoop or get 3/4 of the pot are true monsters. While scooping is the best-case scenario in Omaha Hi/Lo, it's much more important to lock up the high portion of the hand in Pot-Limit games because of how expensive playing for the low can be.
While something like a naked A-2 can be a very strong PLO hand before the flop, I see a lot of people get in trouble with this hand on later streets when they feel committed to put their chips in the middle in hope of hitting their low. Without any potential for hitting the high, these players are putting themselves in situations where they can easily go broke.
In PLO, the best A-2 hands are either suited or have good connectors like 3-4 or 5-6 that will give you straight draws. If you flop something like 4-5-9 with a hand like A-2-3-6, any Ace, 2, 3 or 6 gives you a straight, as well as the nut low. However, even if you have the A-2-3-6 on a flop of Q-9-5, you have to fold if someone else makes a big bet as it's likely they've already made their high hand. Putting your chips in the pot in hope of chopping is not a worthwhile play.
Pot-Limit and No-Limit Omaha Hi/Lo are all about the nuts. If you're not holding them, you should be looking to draw to them. If you can't do that, you shouldn't commit your chips to a hand – especially when your best result may only be winning half the pot. If you're in a hand and are just playing for the low, my advice is to muck your cards and wait for a more profitable situation.