I personally loved the movie. Yes the pacing is a bit all over the place and the action isn't quite as memorable as DoFP, but I never found the X-Men movies to be known for their jaw-dropping action scenes (Quicksilver withstanding). Yes, that even means the raid and Nightcrawler scenes in X2, which are both considerably dated now. These movies have always been about the characters to me, and this new prequel trilogy in particular has done a much better job of exploring those friendships along with the themes of family and betrayal (thanks to Fassbender and McAvoy).
This is still the weakest of the 3, landing right below First Class for me, but it is still very strong. My biggest gripe at this point seems to be the constant feeling that each movie is about the X-Men LEARNING their powers. I've seen it film after film now and I'm getting a bit tired of it. That and (SPOILER, but not really) Magneto constantly flip flopping between sides. But those are minor gripes for a movie that at 140 minutes, doesn't feel too long. The 3rd act is a bit messy, but the first 2 are great and devote an appropriate amount of time across all characters (except Psylocke).
Overall, a very fun time at the movies and a good choice for the Memorial Day Weekend!