I replaced 28-135 after half-year using on 17-40 f4 and started
to feel myself realy comfortable.
I guess Canon's engeneers need to learn from Olympus how to make
middle class zoom lense with such focal range.Before my Canon 10D I had Olympus E-10 with 35-140 mm lense - so this Oly lense can easy
bit 28-135 even without IS and USM!!!