I replaced the screen on my SQB with a Beattie screen which has gridmarks and a split image rangefinder -- it's brighter too and I'm very happy with it. The grip with the thumb winder is great too and all the PS lenses are fantastic, particularly the PS 50mm and the 110mm macro. As mentioned, the backs are the things to watch -- I have one that chews up film -- scratches down one of the edges -- but the other two are OK. There's a school of thought that the SQA / SQB are more reliable than the SQAi which occasionally suffers from battery problems (it takes lots of little batteries instead of a single big one). Not sure how true this is but I've had no problems so far with SQA / SQB.