We had a FastTrak Super Duty and we loved it. Handled anything we threw at it. I would almost say, without knowing the price differenc, if you can go for the SCAG in terms of $$ then you should. You can never go wrong with SCAG and I have heard people say the cut quality on the Hustler isn't miraculous.
Of course we thought it was great, but that's all we knew... We had no experience with any other ZTR brand.