I purchased a 360 gallon acrylic tank from one of their distributors and I am happy with it. Tenecor is well known and in my research I did not find any major complaints with the company other than sometimes exceeding their delivery time.
My brother in law picked up a used 175 gallon Tenecor tank. I think it was custom made since it has a one piece front and sides (curves on edges). For a tank that's 3 feet high, it's surprising that there is no bowing. I'd definitely recommend Tenecor, even though I'm a fan of glass tanks.
I have also had great experience with Tenecor tanks. I am on my second tank from them (1st was a 55, current is a 100) -- no problems at all with either one!!