A lot of the answer depends on what you are going to be doing. I have a Delta and kind of a love/hate relationship with it. I love the power that the 15 amp motor has but hate it that it occasionally pops the circuit breaker when it starts up (easy to fix, I know). For really serious woodworking, you will need a better fence than comes with either. Since Delta also makes an excellent add on fence, it is probably easier to add this to the Delta than to the Ridgid. Delta has throatplates available that fit around various blades well, but they don't fit into the saw all that well. An aftermarket throatplate is probably in order and I don't know about the Ridgid's.
Watch my favorite builder, Norm, and then get a good book on making yourown jigs. The sled for crosscutting wide boards is invaluable. You can make a jig for making the cheek cuts on tenons for the price of some scrap wood and one hold down clamp. A tapering jig is also cheap and easy to build and it's interesting to note that Norm uses one he made but obviously could get a commercial one. Do make a selection of push sticks. These are easy projects and let you feel a lot safer when you are working with no blade guard, as you must with many cuts. And the Delta bladeguard is not easy to set-up or use. Can't speak about the Ridgid. Dust control is another issue and I just saw an aftermarket rig that looks like it will work well but haven't got one yet. Sorry that I could not give you more in comparison but maybe this will give you some ideas of questions to ask and solutions for some things that will arise with either.