I thought you needed a fairly beefy machine anyway if you are playing Star Citizen?
The Rift is about £600 compared to the VIVE's £760, but you are going to be wearing it on your head. This is like motorcycle helmets. Nobody can tell you which one is more comfortable because only you have your shape of head.
The Rift is lighter, and the integrated headphones make it a doddle to put on.
The VIVE is bigger and has more padding to make it comfortable, and their tracking system works over larger areas, but is more difficult to set up.
Pros and cons.. The best way to decide which one to go for is to stick both of them on your head. A PC shop might be kind enough to let you demo them, or if you have a chance, get along to one of the Elite: Dangerous get togethers.
The rift and vive are the same weight now http://www.roadtovr.com/htc-vive-we...n-original-headset-vs-oculus-rift-comparison/