Let me start out by saying I have a 50 Guardian, 50 Shadow and a 50 Marauder (Imperial Sentinel). Guardians can be very frustrating in PVP. Everyone seems to know exactly what to do to take you out. And fast. But it's also my best geared PVP toon. I love the class, it's just weak in PVP. Marauders/Sentinels are one of the best PVP classes. They have a lot of utility, do a LOT of damage (LOLSMASH!) and are quite surviveable. Shadows are fun 1v1 because pretty much no one can beat you, except maybe a well geared Vanguard/Powertech that knows what they are doing. But I find the rotation to be a bit boring. That and if you've ever got steamrolled by a premade that's running nothing but Assasins/Shadows, you learn to hate them. Even if you like playing them. In the end, you need to play what you like. Just be prepared to appreciate the following: Guardian - You'll be dead. A lot. But a fun class. Hey, Obiwan was one! Sentinel - Tons of fun. But everyone else is playing one. Shadow - Good 1v1 and Huttball. 2 or more and you're toast.