I think by number of solos, counting a solo by one guitarist that immediately goes into a solo by another guitarist as two separate solos, they play a high number of solos. But they don't spend a lot of time soloing. That's because, unlike a lot of metal guitarists, Adrian, Dave and Janick seem to prefer playing a brief, tasteful solo to embarking on a minute+ long affair. Consider For the Greater Good of God, on AMOLAD. All three guitarists play solos, each going right into the other. But the whole solo section is only around a minute long, because the solos themselves are compact. I would bet that the median length of an Iron Maiden guitar solo is less than thirty seconds. I think the longest single guitar solo in any Maiden song is probably Adrian's in Stranger In A Strange Land, which is a) an awesome solo and b) not wanky at all. I think the fact that all three of them play compact, tasteful solos is another thing that makes the three guitarist thing work so well. Not one of them feels the need to go off on a 90 second shredfest at any time.