Actual difference is larger than that, though. Because the ATN130E/132EP not only already sports the tapered instead of the straight alu cantilever variant - but it's also got a much nicer diamond with rectangular instead of round shank and a very well polished, true elliptical tip, while the tip of the ATN120E/122EP still is closer to being "pseudo-elliptical". Or in other words: Under the loupe the stone of the ATN130E/132EP looks more like high quality FineLine than a standard quality elliptical.
JDN: I'd suggest to try the ATN130E/132EP and gather your own impressions. Not only, 'cause I'd expect you to enjoy its sound, but also for the practical reason that the ATN130E/132EPs aren't made anymore, while the ATN120E is still is a current product and won't disappear anytime soon. So I'd deem it smarter to try the ATN130E/132EP, while that's still quite easily possible...
Well, and as for the sound: To my ears the ATN130E/132EP does better than the ATN120E/122EP in practically every aspect. That also includes more detail, but presented in a smooth rather than an "in your face" way - like a gentleman with more refined manners, but presented with ease in a natural, relaxed way, without leaving an artificial impression.
Greetings from Munich!
Manfred / lini