I'm test driving some Columbia pants from Bass Pro. They have cargo pockets and SPF 50. They're not the ROC pants, and they're not convertible. Very lightweight. Temperature dropped from 65 yesterday to 25 today (first day I walked out of the house in them).
If I can figure out what they are, I'll post an Amazon link.
Note to self: start reading sig lines. They're actually quite amusing. :D