How's the lag for you in the regular game since you haven't done the DLC yet?
I got unplayable lag early on in Honest Hearts. But the Save/fast travel -reload worked most times.
I get unplayable lag in Freeside and Vegas strips after long periods of play. Sometimes even inside casinos. Fast traveling usually fixes it.
If fast travel doesn't work, I quit out of the game and reload. If the game doesn't let me quit, I do a hard eject from PS3
Restarting PS3 , the last straw method, hasn't failed me yet.
I'm level 30 now, started with FONV saves and overwrote with FONVUE saves. Haven't tried the other DLC
I have noticed that I encounter almost all of the PS3 specific quest bugs listed in the Wiki. LIke the Boomer History kid, or the invisible wall in NCR station bugs. Thankfully reloading has worked/fixed for me every time.
I have also had at least 5-6 hard freezes but I've put in a lot of quests/hours on UE so basically it has been playable for me.
Honest Hearts was great, loved that DLC. Hopefully when I get to level 40 game keeps surviving.