Hi, I did my fair share of searching and I couldn't come up with any answers to a few questions I have about the EHX Small stones, are there any advantages to buying the green sovtek small stones? if so why do they usually go for cheaper/about the same price as the newer ones? what are some opinions on purchasing: A. A newer USA EHX small stone with the analogman mod B. A brand new USA EHX small stone C. A used green sovtek EHX smallstone thanks everyone!