Checked my K5 (early s/n 3827xx from SRS). Sensor is clean but for a few insignificant marks; lesser versions of the ones seen on this forum. I would never have noticed these marks had this topic not been raised and they will present no problem to me in the future because they are essentially invisible. I dare say my istDs and my K-m (great cameras both) have similar marks also - not checked them.

50-135, 9 months, used regularly, no probs.

If there's any left, I'll take one too. I'd even take an extra as a present for my dad. Jon, Peak District.