They are all good, the live album at the Budakon is a good start.
Saw UFO on their tour last year. Saw them when they reunited with Schenker in the late 90s and it was one of the best gigs I have been too. Not so the following year. There was a note on the door saying the gig was cancelled. The previous night Mogg and Schenker had come to blows on stage, never to reunite. A great shame.