SR - is it worth it?

On my honeymoon, back in '99, I bought an affordable dslr. I stayed with that manufacturer throughout the years.

Once digital became prevalent , I bought the istD. Nothing but problems and considered giving up the art. Years later we had a baby and I had a renewed interest. I bought a Sony HD Camcorder that took good stills and I was reinvigorated to take even better shots. I started looking at segway cameras at the cost of $400 but in the end up saving up for and buying the K-5 (when it was nearly full price).

Sorry for the long lead in but, now that the lens market is is leaning towards OS and Pentax lenses are so pricey, I have to ask, other than affordable weather sealing, what is the benifit of staying with Pentax?