If you're only bringing one light, don't bring a surefire unless you want to haul around alot of extra batteries. One of the UKE's or Princeton Tec's will do. If you're bringing another light, then any of the 6V surefires will do, with the M2 on top for the shock-proofness. Personally, I've brought my 6P backpacking to supplement my Petzl Tikka. The combination worked fine. The Tikka was great for general camp duties and bathroom runs without having that yellowish half-dead battery look that the 3 or 4 Petzl Micro users had. The 6P was only used for about 10 minutes the whole trip.
My new combo is a E2, 1 set of spare batts, a Petzl Zipka, an ARC-AAA LE, and a Photon 3. If I needed a real waterproof LED light, I'd use either a PT Matrix, switchback (if it ever comes out), or a handheld LED light.
gm