Just from looking at it on the link you provided (*DISCLAIMER - I HAVE NEVER SEEN THIS PRODUCT IN PERSON) I have a couple of would be issues.
First in the application guide, it seems that they've only been made so far for the wider full sized trucks... regardless of manufacturer. I don't see ANY gates for "compacts"... not the Canyon/ Colorado, Ranger, Dakota or Frontier. I doubt the Tacoma would get any special consideration. I would dare to say that when a Toyota application comes out, it'll be for the Tundra only.
Second, when the tailgate is open, the surface of the X-Treme Gate appears to be a couple of inches higher than the bed floor. Not important though if you don't need or want a level surface all the way out to the end of the open tailgate.
Third... Just looking at, the thin panels seem to me like they would lend themselves to rattling in both the open and stowed positions. Perhaps the design prevents this, but I would want to see (and hear) one in motion first. In the open position especially, it seems the buffeting wind would play hell on those panels.
Fourth, you say it doesn't have slots that thing can fall through. If you're concerned about small items falling through, it does have a gap. The gap appears to be a few inches by a few inches right near the hinge area on the tailgate. Not sure if that would be an issue for you or not.
Finally, I wouldn't get too hyped over this thing yet. Like I said, they have to make it in a "compact" size first.