The concept is entirely unique in itself and I think the crew put a big effort into making it all come together. The acting is okay... Be aware that the plot is too confusing and complex; i wasn't satisfied in a single watch... and the dialogue was hard to catch in some scenes.
The complex concept could've messed it all up, but Nolan made it work well and seamlessly together. Also, Nolan likes to keep a lot of the stuff from the viewer until the end.
Anyways, I think it's a Really, Really good watch.