I have the 780 (was able to get it on sale around last Feb. It appears that DeWalt puts their tools on sale about a month after New Years). I think you did fine getting the one without the XPS.
The saw has some faults:
First CAUTION: DO NOT trigger the saw the first time with the saw down and locked!!. When making the very first cut (with or without wood), trigger the saw with the saw up, pull it all the way out, and then lower it all the way down and push through the cut. There is a plastic piece in the bottom of the blade trough that just touches the blade. If you have the saw down in the forward position and trigger the saw, it grabs the plastic and can rip it up through the insert and possibly tear up the plastic blade shield. This has happened to several people (per remarks on the web reviews) with some having significant damage to their new saw. If the saw is running when lowered, it will cut a groove in that plastic piece and cause no further problems.
Although I have the XPS sytem, for exact cuts I still scribe and set the blade to the line. The XPS is a blade shadow, so shows the teeth when the blade is not spinning. This is fine if you register the piece to the outside shadow of the tooth with the blade touching the wood. However, when the blade is spinning, especially with the saw up, the shadow becomes primarily the blade plate, not the outside of the teeth. So when the saw is lowered, the cut extends over the line. This can throw you off if just depending on the XPS for making multiple rapid cuts.
The saw kicks up significantly when triggered (this applies to the 799 as well). No problem once you get used to it as long as your work is secured well. Problem is that the hold-down clamps are about totally useless. They wobble, and have the tendency to pull the work away from the fence when tightened. For thicker lumber, the vacuum port will hit the work when the saw is pulled toward you all the way, and will pull the work away from the fence even with the clamps tightened. I use a push stick to hold the work, but it is a less-than-satisfactory work around if you have the saw mounted on a portable stand.
Chip/dust collection behind the saw is good only if you connect to a vacuum. Be prepared to pony up another $20 (for 1 1/4" hose) + another $15 (for 2" hose) for the adapter(s) to connect to the vacuum tube. I did not see much difference between using a 1 1/4" and 2" hose size. You will still get chips, etc on the saw table and around the front.
On the plus side, the saw is powerful, and the cuts are very precise in all planes through the entire travel of the slider. It can be dialed in on all planes (vertical horizontal, bevel, etc) to give very exact results. Trigger/handle fits well for either right or left hand operation. It is a solid, well designed saw with the exception of the hold-down clamps.