Having watched all three X-men movies (with questionable merits) and Wolverine (my mind is split on this one), I had no expectations - it could have gone either way, mostly because Matthew Vaughn does that to you. Here we have a guy who directed only 4 movies (so and so ones) yet who produced Snatch and Lock, Stock and Two Smoking Barrels - these last two could only mean that the guy knows what he's putting his money into and on that level, First Class had the potential. However, he is also the guy who financially supported Guy Richie in that shockigly, disgustingly, hillariously bad enterprise called Swept Away. Therefore, Vaughn was a gamble.
And what a gamble!
It doesn't happen often that I give kudos to movies but this one has my approval. For once, sitting for two and a half hours did not prove to be a problem. On the contrary, it was a joyous experience well worth another prequel (note: coming from a girl who hates prequels).
I wouldn't change a thing. Music was phenomenal, script was excellent - for a change, there were almost no plot inconsistencies and the choice of actors was up to standards (mine, at least). The story of how Professor X and Magneto turned into foes after being friends is well-written, well-directed and well-acted. James McAvoy, as well as Michael Fassbender (unknown to me until now) did a hell of a job.
X-Men fans will appreciate Rebecca Romijn's cameo as well as the one with Hugh Jackman (although I failed to see the necessity for the later - note: coming from a girl who adores Wolverine as much as she loves Mr. Jackman).
So, if you have not seen it by now, what are you waiting for?!
8 out of 10.