Looks to be very similar and just the precursor model although 'I think' an XBR is supposed to be somehow better than an XS:
You might compare the reviews/specs doing model number searches.
Hopefully a gamer will step in and give you some gaming-related insight. There's also the issue between 1080i and 1080p native display capability between those CRTs and LCDs, resp. But I've heard the gamers love the CRTs - low input lag and great PQ (color saturation, blacks, contrast, etc.). And those particular Sonys have the Super Fine Pitch (SFP) picture tube for better horizontal resolution than most other TVs.
I've never heard the Sony audio but I suspect it will kick the pants off a flat panel as it's impossible to get any decent acoustics with that thin of a cabinet. My Panny 34" HD CRT kicks butt in the sound department with 5 speakers and acoustical waveguides built into the cabinet plus surround porting out the sides.