There's no 'best' necessarily. It depends upon your space requirement, budget, rack height, etc. Any of the canvas tents (CVT, Tepui, Ironman, ARB, etc) are coming out of the same factory in China so you're getting the same basic design. Each brand does have different colors and features (i.e. skylights, interior lights, etc). I believe Ezi-Awn comes from a different factory in South Africa, but that's approaching hard shell price level.
I've ran both a canvas tent and a hard shell tent (Alu-Cab) and the hard shells are by far the easiest to use, though they are not as space efficient.
Also keep in mind that dragging around a RTT all the time has its drawbacks. Do consider a ground tent (i.e. OZ Tent) in your selection decisions.