The advisement for this film said strong, bloody violence and strong language and that really is not wrong. I have no particular objection to swearing and even a lot can be used in an effective way (think the opening of Four Weddings as an example), but in this case was almost constant throughout the film which meant that to me, anyway, it lost it's impact and I felt it became a really lazy way of showing the difference between an inner city London working class Eggsy, and the wealthy, upper-class characters. The violence was also quite a lot stronger than I had anticipated, and some of the scenes, notably the set piece in the church, draw a few gasps from the audience.
And I think this is partly to do with the advertising pitching of the film. The poster features Colin Firth prominently, and he is in a lot of the trailer, the film looks like it might be a throw back to Bond films of the 60's and 70's, and the audience at the screening I went to, definitely had a much more advanced age than I think the film is actually aimed at. I probably wouldn't recommend it to my mum, which is a shame as overall it is good a looking (no-one rocks a suit and glasses like Colin Firth!) because of the violence and constant swearing.
This out of the way, I think there is a lot to like in the film. It is very stylish, and if you are a fan of those 60's/70's spy films, there is a lot to enjoy with many nods to Bond, Man from U.N.C.L.E., Danger Man, The Avengers etc. There are several great set pieces and a lot of well-paced, and towards the end frenetic, action sequences which meant I was never bored whilst watching it. There are also enough laughs
I liked Gazelle, the bladed side-kick to the main villain, and I especially liked that she wasn't given any kind of tragic back story, she was just a badass villain. I would have liked to have seen the character of Roxy (who is following a similar to journey to the lead character of Eggsy) developed more, and I especially liked the fact that she was never set up to be a romantic interest for the lead.
However, I spent quite a lot of the movie cringing whenever Samuel L. Jackson's character, Valentine, was on screen. His slightly camp, lisping villain made me feel very uncomfortable, didn't we move on from that stereotype a long time ago? Apparently not.
I also think the end of film with a Swedish Princess offering herself as a reward for the lead was very unnecessary. I can understand why it was put in, after all Bond always gets The Girl, right? However, the film several times says that it is about subverting stereotypes and this ending didn't sit well with me.
This film also features Mark Strong doing a strange American/Scottish accent.