I haven't seen much of Moses. I've personally seen him play twice (in actual games), and I saw him play basketball. I will say this this, the kid was not on a very good HS football team, but he hung in their and looked tough. He didn't come across incredibly impressive, but I don't know if anyone would have looked very impressive on that football team.
Here are the few things that I know:
(1) He is legitmately a large QB. I believe he is every bit of 6'5" 230 lbs (I know Weber is listed at 6'3" 220, but Moses is more than 2" and 10 lbs larger than Weber).
(2) He is certainly athletic enough to play QB. I think some people on here are confusing "large enough to play elsewhere" with "too large to play QB". In my opinion, Alipate could easily walk around at 255-265 (at the end of his career) and still be pretty athletic, he is simply that big of a kid. So the idea of him playing elsewhere could be appealing if Gray is what we hope he is.
(3) He has a big arm.
The rest is...well...unknown. None of what I said means that he will be a good QB or has any chance of beating out Gray. It's sort of an unknown. From the people that I know who are more in the know with the program, it seems to be a mixed bag. Usually I hear the same things coming of the different people I know (Hageman is going to be a monster, Tinsley might be the best player on the team, etc.), but I have heard great and very lukewarm things about this kid from different people.