The Boulder is conflicted.

Taken from the final episodes of K-On season 2 and expanded to include the Graduation trip to London, our favourite light music club is readying for graduation, but not wanting to leave Asuza without giving her a parting gift, the rest of the band use the trip to London to gather inspiration and create ever lasting memories but the girls find the culture shock of London a little complicated.
My main complaint is that they didn't spend nearly enough time in London, considering the pain staking effort to animate actual locations from the city, it feels disappointing that only half the film was spent there while the other half could've been done in the series, it leaves an ending with no epilogue, something a show like this would benefit from as we kinda want to see if the now adult light music club still make music together although the music video style openings at least imply that at least Mio makes it as a music sensation.
Sub is much better in the movie but the dub is otherwise high quality.
Final Verdict: I maybe wanted a better send off for K-On but the film itself is at least enjoyable.