Deus, I wouldn't neccessarily say more euphoric. Definantly more of a body high than methamphetamine, though.
In my experience, 4-methylaminorex has more mind-altering properties. Instead of just acting as a stimulant, it has some characteristics of MDMA. I've only taken it a few times, but every time I took it, instead of getting talkative and sociable like I do on meth, I got very introverted and introspective. I would get very quiet and see different perspectives on things and just think for hours and hours. The other thing I noticed is that it immediately made subtle visual changes. It's hard to explain, because as I said, they were subtle, but there were definantly differences in the way things appeared, particularly colors.
I would imagine the euphoria itself has much more to do with the users state of mind than anything.
I prefer meth to 4-methyl.. the 4-methyl gave me too much of a head trip. Meth is just more fun to me.