Glad to know you did hear back from Todd.
In terms of what you get for spending more, there’s been at least one forum discussion comparing Jay’s cdt2mk3 and cdt3. It shouldn’t be difficult to find.
From what I understand, the laser assembly in the cdt 3 is more robust-- more metal, less plastic. I have to say, though, that I’ve never come across any mention of the cdt2mk3 laser assemblies failing prematurely. Doesn’t mean it hasn’t happened but neither do they have a reputation for this.

