Having read through all the helpful information posted on this forum I decided to take up the offer from Amazon UK for a K-S1 + 50mm f1.8.
I have been using a K-01 along with my Canon 600D for the last couple of years but never felt like the K-01 was getting it's best use, I only had the 40mm XS with it.
In January I purchased a 16-85mm to go on my K-01, at first it was good in good conditions but once outside the arms length approach and composing through the viewfinder saw the keeper rate fall very quickly, I thought I had made a very expensive mistake in getting this lens but soldiered on with indoor tripod mounted photos.
Then I saw the K-S1 fall in price, I did my research and pondered, and deliberated......then pulled the trigger and bought one. As soon as it arrived and I attached the 16-85 I knew (this time) I had made the right decision.
The size is slightly compact compared to the big ones, this I don't mind as it fits in my hands. The grip, having came from the K-01 is a lot better, it is very fast at focussing TTL and live view plus the pentaprism is a godsend. I know pairing a WR lens on a a non WR body may seem odd, but I suppose I'll just have to dodge the rain drops plus the K-S2 was nearly twice the price body only.
Here's hoping for a happy K-S1 future.