Originally posted by PentaxPoke
Also, do we need to show this again?
[YT]http://www.youtube.com/watch?v=ngUcQUchHEU[/YT]
no, we don't. without knowing the conditions of the camera's, lenses and what they were pointed to, this video doesn't say squat.
Pentax's AF has its weakness in low light AF and tracking, but it can be made to work. a little skill, a little anticipation of the action and a fast lens.
in my experience, K7 and Kx are much better than the K20 or k10.
if i were the OP, i'd try to get the 50-135 fixed first. explain the situation to pentax or talk to your credit card for that extended warranty.
i certainly have had much success shooting indoor basketball w/ my km, kx and 50-150 sigma. i've also had success w/ a sigma 17-70, only fact is, sometimes 70 is a tad short and it's already at f4.5
if you can borrow or rent a kx, give it a try. just make sure you use a fast lens.
if you can rent a canikon, give it a shot, if it works better for you, well, you make that decision.
good luck.