OEM modifications to Android really affect the end-user (mixed-bag) and from my experience the worst to best tends to be:
-Blur
-Sense
-Stage UI
-TouchWizz
-Pure Stock Unadulterated Google Android
-CyanogenMod
-MIUI

And despite my distate to Samsung's cheap-plastic experience, I think its much better than LG/Dell/etc and HTC's wishy-washy soft metal uniody-thats-not-unibody. It's also the thinnest of them all.
Motorola gets top scores for physical sex appeal though!