I have only used a light duty scoop that I put together at home and destroyed 7 hunts into the season AND my....
Stealth 720i
The 20 degree angle makes digging so much more enjoyable over the 90 degree angle. And that scoop is really massive! I had no idea it was so big until I saw this pic my wife took one day...
I have friends who have RTG's and are happy with them, but for me it's the 720i...
The RTG is a great scoop but the round design can hold soupy wet sand making dumping it difficult. In the water they are great. The Stealth is heavy as heck without a load of wet sand but there is a cult following on those scoops. There are better scoops but those who push the Stealth have never used those better scoops. I guess the best scoop is the one you own because you don't know any others. Buy what you think is best. It won't be as good as mine if you buy either of those so IDC.