I purchased the ST2800, 110 inch saw track from Evolution. One section was bowed 0.005" in 4 feet, the length of my Starrett straight edge. The other was bowed 0.002" in 4 feet. I consider 0.005" acceptable, but not outstanding. The track ends were badly out of square. That was easy to correct but should not have been necessary. I know Evolution recommends leaving a gap between adjacent rail sections when joining. Better workmanship would make that unnecessary. I have no experience with other brands of track so I can't compare. All things considered, I find this track adequate for its intended purpose.