I'm using the CM Cosmos right now. There's lots of room inside. it has its ups and downs. I will say that it's more than likely going to run hotter than your antec, but not enough of a difference to cause problems. Probably only a few degrees. Wire managment was a pain, but with a dremel you can mod the MB tray a bit to help.
my old worklog has some pictures with stuff inside for a size idea.
WC finished, CM Cosmos. (Pictures)
Its probably my most preferred case to date, and at that price its a steal.