You can probably use that valve, I can't see why not. I personally like running such a valve, although GT routinely chastises me for it (A solution to a non-problem). I will agree, I've never seen one of mine "pop-off"....but still cheap insurance. The best insurance is one you never need.
The opening and closing of the T-Valve is another matter I've had many issues with. Dirt and sand mess them up quick, so a Sea-Strainer should be used on the incoming water at the jet in all cases anyway, and I've usually ended up installing a driver controlled micro valve so I could simply shut the water to a trickle while in NWZ's or extended idle speeds. Seen and milkshaked more motors I think because at one of our local lakes, there is a 2 to 3 mile NWZ up the channel to a popular beach to hang out, drink beer, and bench race. The water there is flowing, not unlike the Colorado, so a lot of junk in the water in that area.
Ray
