Purchased K5 with 18 - 135mm zoom, DA 35mm F 2.4 AL and the AF 540FGZ flash about 3 months ago. Great compact kit.
Love both lenses - portable, sharp if you stop down a little and excellent images.
Still learning how to get the most out of the flash but have had excellent results as fill flash in situations with strong backligh and midday summer sun. Australian summer daylight can be very harsh!!!.
I am very happy with both lenses and the capability of the K5. Dynamic range is just amazing and I am getting image quality that was out of reach for most people when I first learnt photography using a secondhand PRAKTICA IV and then a Nikkormat FTN many years ago. Forget the good old day - current technology is just fantastic.
But don't forget to learn, or in my case rethink, the basics of appropriate appature, shutter, ISO and focal length for the image you want to create and enjoy just taking lots of photos.