Thanx for the responses. Sam, was the site you mention prone to noise? I assume your solution worked?

This is for a for client who is thinking of taking an extra floor of a loft-type building that used to house a small printing plant on the ground floor and basements. All the wiring in the floor they occupy (directly above the departed printing plant) is shielded as far as I could tell from a rough inspection.
They want to move the equipment closet to a bigger one on the floor above. I'd just rather install xconnects in the old space and move the equipment to the new closet. I figure the cost of extra STP is roughly similar to laying new UTP wire everywhere.
One thing I don't feel comfortable doing is mix STP + UTP on the same run. Let me reiterate that noise seeping into the wire from the presses is no longer an issue. I've never seen shielded xconnects either, but I was hoping I'd missed something.