I've had the Jet sharpener for about a year and it works fine. On the other hand, I use my diamond plate and water stones with a Veritas Mark II jig most of the time. It's easier and quicker by hand.

One of the things I dislike about the Jet, and may be the same for the T-7, is that it can take some fiddling to get the setup right so the blade is ground square to its edge. The Veritas Mark II is less prone to errors.

With the grinder, I don't just put the blade on it, turn it on, and work on something else. I keep the blade moving left and right so I wear the surface evenly, and apply a little hand pressure. So I'm standing by the machine the whole time.