[kenyee]

SDM focusing on the Pentax da* 50-135 (a lens I own myself) was just as fast as comparable lenses from Canon and Nikon?

I think Kresica did a great real-world test, but I'm afraid "comparable" isn't what I'd call the lenses...a 70-200 probably has more mass to push around. I blame Pentax for not making a 70-200/2.8 SDM though, not Kresica for messing up the test

Kresica:
the Pentax AF tracking system is ok if you go sideways, but if you have objects moving towards you (e.g., a baseball player running at you down a baseline and you're at the end base, and you just hold the shutter down to do continuous frames), it's not as good as the Canon system. The Canon 1D users expect all frames to be in focus when you do this test; I'd just be amazed if 60% were in focus

[Kresica]

the Pentax AF tracking system is ok if you go sideways, but if you have objects moving towards you (e.g., a baseball player running at you down a baseline and you're at the end base, and you just hold the shutter down to do continuous frames)

Yep, you are wright!

[jonny1986]

Never had a problem with AF speed shooting fashion in studio or on location...(To Be Sung Loudly) Dah Dah!

I agree with you benji. I have decided to do photography full time. It' s very difficult but up to now my pentax k10d has been very good in all assignment.
The last week i went to shoo a car event in Italy. I have found that the autofocus is very accurate and fast also with my sigma 105. Probably the continous sucks a bit respect a nikon d300 or d3, but i don't shot primarily sport so i can live with it ( anyway i think the most important thing is to improve the fps, at least 5).
My photo has been published in an online newspaper and i'm very happy, and love the colours and i think i tried to give a beter perspective than usual shots.

here my gallery:

Il Motor Show invade Bologna dieci giorni di passioni e disagi | il Bò Emilia
i think i have done a good work. I used also a vivitar 285hv with a stofen and gel, sometimes i have another vivitar 285hv optically slaved. I haven't seen any other pro use a softner, and for me this is very funny cause i think sto fen sucks energy but give incredible results....
So for my job pentax is very good. next year i'll invest heavily in pentax gear and in case in a medium back if the activities improves.

here an example, pentax k10d sigma 105 2,8 with vivitar 285hv with stofen