Lens Reviewing and Pentax Compatible UWA zooms

Hopefully some of the talent around here can help me out with a few things.

Recently, I got hired on to be a staff writer/lens reviewer through a photography forum. The job seems fairly simple, easy to do with my current living situation, pays decently, and is a great way to use lenses in 'quiver niches' that I don't have filled at the moment. I don't know what to really expect other than writing articles that fairly evaluate lenses from a technical standpoint as well as serve to sell lenses. Has anyone around here done this kind of work before and have any advice?

I'm also looking into FF-compatible wide angle zooms, specifically the Sigma 12-24mm F4.5-5.6 EX DG in any of it's versions. Has anyone here used this lens on FF/APS-C and what did you think of it? From what I can tell it is currently the only FF compatible UWA zoom available in the K mount