The K3 was a great improvement in IQ over the already very good K5. It has two issues though that it would be good to fix:
- The infamous mirror-flop bug. However, this only happened once to me, and was an inconvenience for less than a minute, so it's not a big deal. May have been (partially) fixed by firmware 1.11.
- The noticeable shutter lag when using P-TTL flash. This disturbs me more.
I am in no rush to jump to FF. A few of my lenses are FF-capable, and I'll consider getting a Pentax FF DSLR body if one ever emerges in K-mount, but I value the relative compactness of the present K3 setup.