TUS has one. It's shared with UA, AS and US. It works great during the long lines in the morning. Just kind of work your way in to the line at the top (at least that's what I do on the WN side).

PDX has one as well. It's a shared line with the rest of the D/E concourse. Still can save some time.

Every time I've been there, staying as far left as possible is the quickest route thru security.