Firsthand experience with Pentax K100D Super or K10D, or Samsung GX10 ?

Our picture needs are quite varied. We do some indoor pictures, both for
room portfolios and normal shots of friends. We also take a lot of
landscape and wildlife shots on hikes. Most importantly we wish to have
more success with action sports shots, likely at a pretty good distance.

We have been guided towards a Pentax K100D Super as a first DSLR. The 6.1
MP is fine for us I believe, and the fact that the anti-shake is in the
camera body would potentially save us a lot on AF lenses.

Recently while testing out the K100D, the salesperson suggested we look at
the K10D, its' big brother. Lots of stuff we don't need, but the 10 MP and
the better quality lens is appealing. Is it $270 more appealing, I don't
know.

The same salesperson suggested that we consider the Samsung GX10. Now that
Samsung and Pentax merged, the GX10 is the same camera as the K10D, with a
few cosmetic differences and comes in around $100 cheaper. It also has a
slightly nicer Schneider lens.

My biggest concern is how the two cameras (by this I mean the K100d vs. the
other two) would work in daylight, taking zoom shots of fast action about
200-300 yards away. I think pretty much all DSLRs will do OK for our other
needs.

Or should I just be looking at a super-zoom point and shoot? I know both
Canon and Nikon have good ones for a couple of hundred less than an
entry-level DSLR.

Any advice appreciated.