That's good to hear about the Alpha.
Yep, K-01 has flaws, but they are easily overcome, and the IQ is fantastic if you use the camera properly.
I've added some Sigma lenses to my collection this past week - 70-200 KA zoom, 28-80 and 28-200 KAF zoom (wholey carp, I bought AF glass,...), looking forward to using some to film bands at "The Tote" in Fitzroy (Melbourne),.. It's funny the reaction you get from 'serious photographers' when they see the lack of viewfinder, or hear that I bought the camera to do video first and foremost.
Tryed the function where AF is put on the AF/AE-L button, then hit it for AF during video, yeah, don't do it,....