I just got back from watching it, and it was pretty fun! A nice, light comedy heist movie, with the Marvel flair. They really took advantage of the 'ant' in ant-man (I was worried they were going to focus more on just him getting small and popping up again).
I'll probably write more and gush tomorrow, but definitely wanted to get out there that this was definitely let down by the trailers. Despite the change in helm, they really managed to pull it off. Sure, not GotG amazing, but pretty great none-the-less. The characters were pretty spot on (though the villain was, again, pretty under-developed - Marvel is a bit hit and miss with their villains) and the jokes definitely got the laughs.
Marvel has definitely done it again.