As far as The Marvel Cinematic Universe goes, this might be the best entry up to this moment. It builds up from IM3, T:TDW and (specially) CA:WS, and you might enjoy it even more if you watch those movies a few hours before to remind you a few facts. It has the same vibe and humour you might expect from Whedon's encyclopaedic Marvel-knowledge, yet something goes very awry (story-wise) just before the third act (you'll notice right away). Thankfully, the movie recovers and delivers at the very end, barely. Ultron - as a character - feels underdeveloped. and the stakes never feel as high as they might be. This is compensated with blockbuster-grade action sequences and VFX that make you forget that, but the main villain's demise feels like a huge disappointment. You never feel invested into Ultron's innermost tragedy (a flawed vision/programming that creates the whole conflict) that comes from Stark's cutting-corners attitude. This movie feels like an in-between chapter in a great story?: yes. It sets a proper tone for the upcoming Infinity War?: no. At the end, it doesn't really matter: you'll love it, and when you think about it later, it feels kinda hollow.