My own style would (did) pick a 10-20 over worrying about the gap...though I have the 17-50 Tamron and that extra 10mm helps. I'm rarely at the short end of the 70-200, and that's when the 17-50 comes off and it's not the 10-20 going on, so... it's not very often at all. Only for portrait work, where I like to use 75-90mm. In fact, a 10-20 and 1.4x or 2.0x TC could be a whole lotta fun. Anything more and you're really looking at application specific lenses (50 prime, or birding, etc.)
C


