I have both the 24-105L and the 28-135. They're both fine when you play to their strengths. I often use the former on my 5D MkII forits excellentsharpness (big help withextreme crops &/or enlargements). The latter Ikeep onan old 20D for all-around snapshot/candid photography. Creep really isn'ta bigissueif you keep your left hand on the zoom ring (it's a good &steady way to hold the camera). Compose a little wide, then crop if necessaryfor the final product.My biggest issue in a lens will always be relativeimage quality. The L-series lens is worth every penny, but overkill if you only want toprint 4x6 or view on a monitor. I like having both. After all, isn't the ultimate goal to die with the most equipment?