I've had the Powermatic 719t and sold it to get the JDS multirouter. The 719 was a nice machine but even though it tilts it's not as easy to cut angled mortises as on the JDS, and with the JDS you can cut both the mortise and the tenon. I've found that it's sometimes much easier to cut the angles on the tenon instead and keep the mortise conventional. The only downside to the JDS is the set up time. It's pretty straightforward on the regular mortising machines to set up your cuts, and the JDS set-up for the mortises is pretty easy too, but the set up to get the tenon to fit tight takes awhile. But then again it's take awhile to get the tenon right if your cutting to fit on the tablesaw too.
It really comes down to production, if your gonna cut just a few mortises and tenons then a standard mortiser with hand cut or table saw tenons works awesome. If however, your gonna build a set of dining room chairs the JDS is the way to go (assuming your mortise and tenon cuts are all the same-especially if angles are involved)
Don't however fall into the false belief that the JDS is an end all be all problem solver. I've had projects where I've ended up spending more time setting up the multirouter for cuts when I could've cut them quicker by hand. It really excels at production cutting.
Hope this helps