YES!!!
My friend and i have the same UCD 46.
He have saito 72, I have TT 46 pro.
The main difference are:
1. 46 engine is lighter- therefore the Global Freestyle seems better.
2. 72 saito vertical performance is much better and easy to get out from danger maneuvers.

the main difference is in low speed maneuvers when you need more power from the engine you need the saito 72 or 52 two stroke.
For beginners the 46 engine is enough!!!

The two stroke engine are lighter then the 4 stroke engine. this is very important in this kind of plains.

Offir.