I've been riding Moses 633 for 2 years. After first year on small 550 and 590 wings. I absolutely love my 633 wing and have total of about 350 hrs of foiling over 3 years.
Weight is 76kg stripped and use Hyperlink kites.
Today was 5-6ms and I was on 9m Hyperlink with just enough power at low end.
I took out the Moses for 30min to get " warmed up" . It was 4c...
Then I rode Gong M Pro with 40cm stab and 90cm mast 30 min after 30 min on Moses.
After 10 min getting acquainted, I was very impressed. The Gong is a great foil and actually better than the Moses 633 ( pains me to say it!!).
It's a great set up. Only 2 things are negative.1. the foil will not float on side indefinitely like Moses does. 2. It whistles. Theses are small issues that required me to refine my starting technique. The whistles can most likely be solved, but not sure.
Gong M Pro compared to Moses 633: seems slightly faster, better at maintaining speed into, in and out of turns, better stability at speed in all 3 axis, but still as agile or more as Moses 633 in all speeds and point of sail.. Slightly less prone to tip breaches.
I have a 2016 Moses 93cm mast and it has tendency to ' catch' on side chop. My hypothesis is it's due to curved mast and thick profile at base. The Gong sliced much smoother, and stood up to pushing hard to windward better.
I struggled to get started due to being spoiled by Moses floating on side. Plus, needs a bit more forward speed to lift, it's not much. Just a bit more aggressive in kite and you pop up. After 3-4 tries I figured it out.
Doing heel to toe side flying tacks were easier. I think due to speed being maintained better thru turn.
I would recommend the Gong M Pro with 40cm stab and 90 cm mast for dedicated beginners and advanced riders, that will be good to grow on. It's basically a slightly better Moses 633.
If you are more timid, the M Pro with 55cm stab and 80cm mast might be a good step in.