I have a Festool ATF-55. I've tried circular saws and guide systems of many incarnations for a long time, and imo the Festool is hands down the best out there. It's not only the best out there, it's way ahead of whatever's in second place. The guide system is amazingly accurate. If I take some care in placing it, I can cut a piece of sheet goods that shows no gap at the corner when I check it with my Incra square. And I agree with Ian...that plunge action is the berries.
I also have a Grizzly 10" cabinet saw with Exaktor sliding table and HTC roller outfeed table attached, as well as a router table with Incra LS positioner and fence attached as the right wing.
If you wanted to take either one of those away from me you would need to be armed.
The saw I use the most (I can see a path getting worn in the concrete floor) is the tablesaw. Even though the Festool is accurate, the tablesaw is more so. The tablesaw excels at repetitive cuts. The tablesaw can be used to cut tenons with a tenoning jig. The table saw can cut dadoes. The tablesaw can make angled cuts more accurately than a circular saw. The tablesaw can make a myriad of other cuts that I can't even think of that a circular saw either can't or can only do clumsily. The tablesaw is quicker to setup. The Exaktor sliding table is very accurate at crosscutting, so I use it for most of that work as well (gave my ras to my brother cause I wasn't using it anymore).
I should say that I work mostly with solid wood...since I have a bandmill and a good source for logs it's available to me and actually cheaper (as in free). Plus I like the challenges of solid wood, and I think it's prettier. But I'm getting off in the weeds here.
Even with the Exaktor slider and the roller outfeed table, horsing around a 4x8 sheet of anything (even luaun) on my tablesaw is a pain, and the heavier it is the bigger the pain. Until it's manageably smaller than 4x8 I always go fetch the Festool. Think about it...would you rather maneuver that big sheet of stuff through the blade, or maneuver the blade through the big sheet of stuff. Furniture grade sheet material isn't cheap, so it's nice to be able to set up a cut and know that it's probably going to be a keeper...if not, it'll be within a blade width on the tablesaw of being so. The Festool lets you do that. If all you want to do is rough-cut sheet material to a smaller size so you can take it to your tablesaw use anything...a circular saw suitable for the trades, an inexpensive jigsaw, heck use a hatchet.
The base of the Festool saw has a channel that rides on a rail extruded into the guide, so you wouldn't be able to use just any old circular saw with the guide. And as Ian and I have already said, that plunge cut...well, you won't believe how sweet that is til you try it. You know how when you finish a cut with a "standard" circular saw and it's still spinning you look around and say where am I going to put this thing...the blade on the Festool retracts, so you put it wherever you want to and it doesn't go running across the table making tooth marks in things.
If your price point for a tablesaw is $1k, check out Grizzly. Okay, I admit it, I'm a big fan. My shop is very green. Their G1023 (with variations) is a proven design that's been out there for a long time. You could do worse.
My advice would be that when you do your research stay focused on value (and I don't mean just inexpensive) and forget about the "hey look I've got a Powermatic" syndrome. Sometimes to get what you need you actually do need a Powermatic (as in Vaughn's lathe), but not always. And here's another thought for you...try to avoid the "one tool does all" abyss. It's tempting...I have some scars from it...but in general I think it's a bad idea. I bought my first ras because it could do everything...rip, crosscut, dado, plane, drill...you name it and there was an accessory to do that. Problem is, you spend 20 minutes setting up to make a 5-second cut. And 20 minutes to make the next.....etc...and I'd like to meet the guy who thinks tool setup is fun. And the bloody thing was always out of alignment. My last ras was finally relegated to crosscut duty only (before I gave it away, as I said). Specific tools for specific jobs...besides, acquiring tools is part of the fun.
Good luck with your decisions. Relax. Have a homebrew.