I am also in the Denver area, and found your post (and email) most interesting. And yes,
I must be living proof of the need to seal porcelain tile!
I usually deal with Capco; if you live around here I'm sure you know them.
I've been real busy these past few days and haven't had much time to check your site (or go back and re-read your email), or even post to these boards. But I do appreciate your info and will try and spend more time on this soon.
AMJ: Is your product compatible with a previous installation of water-based sealer? Also, would it be ok to use on kitchen surfaces (it wouldn't be anything smelly like WD-40 would it...just kidding )
And yes, Floorcraft, these appear to be polished porcelain....so not sure how sophisticated the glaze is...but there is a 'marble-look' pattern on the tiles.
Welcome to these boards!