Just from my experience I had a timing belt break on a 3.0 on the highway, and it caused no valve issues. Even had someone start one with the cams miss-alligned. Cannot say whether the 3.5 would be the same way, expecially the DOHC though.

1996 SR From the Area 51 Skunk Works. 37"BFG Tires, 5" lift, Rock Track 4:1 Case, Tom Woods Drive Shafts, Oasis Air, Front ARB, lifted gas tank, T-max winch and lots of stuff that cost too much.