I saw this last night with my boyf, and he was a bit worried that he'd picked another turkey after seeing 'Legion' a while ago, but he was surprised that I actually quite enjoyed it.
I didn't guess who the Devil was going to be, I was just rooting for them to die early on because I found them quite annoying. I actually thought the film could stand to be a bit longer, but then I thought the same about 'Legion'. Both kinda similar with the whole devil/demon/god thing, but both felt like they needed to be a bit longer and have a bit more explanation. I was satisfied with the ending too, which is always a bonus.
I thought it was going to be a horror (fright a minute) film, so was pretty pleased it wasn't. I don't like horror movies - not because they scare me - but I don't find them especially entertaining.