Sony Alpha's are actually Konica Minolta's not Pentax. Konica Minolta championed the Alpha (lens mount) with the Dynax/Maxxum series of camera's before being bought out by Sony. They went broke after losing a lawsuit to Honeywell. Something about stealing autofocus designs and such. But I digress....
The short version is thus. Sony bodies are top notch with most of the tech coming from Konica Minolta back in the day, small things like autofocusing when you cover the eye piece are Minolta ideas they still use today. The kit lens that comes with the current Sony Alpha kit are a DT series lens, usually 18-70 and 70-300. To be honest they are not doing the camera's much justice with the kit lens. Upgrade to Konica Minolta's old autofocus series of lens's as they are FAR superior in image quality and second hand ones are easy enough to find for a good price. I'm still using minolta glass thats in the area of 15 years old with my Sony Alpha and getting good results.
Good Buying in my Opinion.
G.