I am a big fan of Bridgestone golf balls and have tried them all. Started with e6 about 5 years ago and am now playing the XS.
My driver swing speed is about 105 and my angle of attack is pretty neutral. For me, RX & RXS launch higher and shorter than X & XS. I prefer the feel of XS over X due to softer feel and better impact sound. All of them are pretty durable (unlike Pro V1 & V1x, they do not scuff too easily from solid wedge hits) and consistent. Since everyone else already gave you the "best" advice (try them yourself), I thought that I would share my experience and preference.