the only thing a table saw is better than a ras for is ripping boards.
other than that, a ras:
1. is much quicker to line up a cut
2. the workpiece is being pushed DOWN and AWAY FROM YOU with a ras rather than UP and TOWARDS YOU with a ts
the most important thing with a ras is quality....a little history (this is my understanding):
at one time, ras was the "one" saw many people had. as the diy market grew, books were written for the hobby builder...which of course, told how to build things with a ras. in response, inexpensive ras' came onto the market.....and this was the problem.
there is a huge ammount of force on a ras, and unless it's really solid and well calibrated, it can be a problem. the cheap ras (ie: most of the craftmans you see available used) are dangerous. after the hobby builders started getting injured, the ras was dropped in favor of the ts.
i have a mid 60's delta rockwell 10" RAS. $100 on craigslit, it's in great shape, and is a thing of beauty. a turret head and adjustments in all directions make any compound cut possible (with a quick switch from 45-90-45 degree cuts). using this is like using a machine tool, not a woodworking tool. i can be incredibly accurate without spending a ton of time double checking everything and making test cuts (a good ts with a fancy fence would offer the same thing).
i have a 8" craftsman ts that i got cheap that i use for a few things...but the ras is "the tool". it can be setup to rip, but the adjustments are touchy, and it's not convienent to do where it is setup. if i have to cutup plywood, i use a skill saw.