I played through from normal up until Act 2 Nightmare solo. Never did a public game. Only did one at that time due to Belial...

Anyway, after that, I played around with some public games. Got lag at the start of any public game. Lag that I never got in solo games. After many many public games, some with bad start lag, others with not-so-bad start lag, I've decided to go back to solo games. When other players join/leave the games, I get lag. Lag that causes my game to "pause" for a few seconds. This results in death at times.

Most recently I was in a public MP3 game with my paragon lvl 30 WD. Others joined ranging from paragon lvl 0-14ish. While they were joining/leaving, I was experiencing lag. Resulted in quick deaths vs what should be very simple things for me to kill.

In hopes that maybe you (Blizzard) can do something about this soon as I've reported public game lag issues before. Followed the suggestions, but still no change in the gameplay in public games.