I use internet explorer- so far no lag. Occasionaly squares start turning white if I start rolling the land around to fast and I get a time out message after using it 5 seconds, but these are fixed instantly when I renew the screen. I do get lag on several "non prototype" games like mafia wars, monsters in the backyard, ect but these simple graphics realy don't seem be slowing the game. Load time is always fast.