Currently, I use three lenses:
I rely most heavily on a 80-200mm zoom and a 28mm wide angle. When necessary, I also use 50mm lens.
I actually setup a separate forum discussion on the three specific lenses that I use. I've had a hard time locating specific information on them, as well as how well they will match up with the K-5.
I'm definitely interested in picking up an automatic lens that is properly matched with the K-5. Indeed, it will be helpful for my wife who doesn't have any experience with manual photography, but who would love to use the camera to shoot the kids, and to take photos around the city. I'd also enjoy it for those moments when a quick photo is in order. But even more, it would just be nice to not have to make mental adjustments in terms of SLR-to-DSLR mm changes! All this being said, I'm not looking to spend a ton of money, as the primary reason for moving to the K-5 has been that my 35mm crapped out on me!
Here is the link to the other discussion:
Need some lens help/advice - PentaxForums.com
Thanks,
Mike