I've recently downloaded the MoP client to play on Frostwolf, but I've had quite a few problems already. I keep falling through the floor in Gilneas, Elwin Forest and in certain areas of the panda starting zone. I've had severe lag to the point where I can't move my toon, but after 10-15 seconds I just die. I'm not complaining about the quality of the server, I'm just wondering if I should bother levelling because if the server has these issues throughout then I don't want to waste my time trying to play.
I'm also having those issues and changing the client to the new enUS one is not solving this. I have severe hole issues all around stormglen and I can't continue the quest line because the holes are just everywhere.
Edit: Just for reference, you need to delete/remove your enGB folder for this to work.