I haven't done any tests,
The Universal just seems softer to me than any clear
I have ever used. The Euro seemed harder.
Either way, I like them both, it's the price that made me try the Euro.
The price is actually closer than it looks when you consider
the Universal with activator makes 2 gallons of clear,
where as the Euro makes 1.25 gallons.
But the Euro is definitely thicker, I reduce it 20%.
(So I guess it actually makes a little more)
The Universal flows better, I'll pick it when I don't want to buff
afterwards. It's great for bumpers.
I still think the Euro is better for dark colors that are going to be buffed.