Are you rendering the game on Hardware settings or software settings? I had the same lag problem but changed the settings to software and it runs much faster now.
I would also recommend you restart your computer every once in a while, or defragment it.
I'm gonna wait a bit to buy it.
Hopefully, this won't be superhyped, only to waste your money for a load if a crap.
But it looks a bit like societies and 4 combined.