I have the Blackstone Tailgater; and love it. Considered the Camp Chef system, but the cost was significantly higher by the time it was outfitted similarly to the Blackstone.
The tailgater comes complete with 2 burners (1 round, 1 "H"), the griddle, the grille box, and fully adjustable legs. Add the carry case set (for all components) and you're up to about $225, vs $300+ for a similarly equipped Camp Chef (base unit, grille box, griddle, leg levelers, case (for the base unit only)). Online user comparisons also suggest that the Tailgater's H-burner gives a more even cooking temperature across the griddle.
As for the quality...although I haven't actually used the Camp Chef, I have looked at/felt it in the store; while a bit heavier, I don't see enough of a difference to claim "apples to oranges". If I was full-timing or using it at home, then perhaps the Camp Chef may have gotten the nod, but for me, the Blackstone is the way to go. The adjustable legs are extremely important on a flattop griddle, ALL of the parts fit into just two carry bags, and so far the quality has proven itself sufficient for "camping" use. Of course, YMMV.