My original Strobostomp suffered from failed jacks, so I bought the SS2 thinking the metal jacks would make a difference. Nope, they cut out so I modded mine by doing some re-soldering and mounted the jacks on the side instead of the top. It works pretty well now without cutting out, but it was a hassle, I hate Peterson and their poor reliability. I've now given the company $400 just so I can tune my guitar well. There "is" a difference between these tuners and ones like the TU-2 and I have noticed it on more than a few occasions. Strobe tuners are easy to use as well and with a little practice you can tune up really quickly during a gig with 'em.
If they had this pedal around when I was tuner shopping, I'd have bought it and never hassled with the Strobostomp:
http://www.turbo-tuner.com/
It's not as pricey, more reliable, just as accurate and it's a true strobe design, not an "emulated" strobe design like the Peterson.
So there you have it. I have a SS2 on my board and it'll stay there until it dies (I don't like spending money on something if I don't have to), but after it dies I'm done with the company. I've heard so many great things about the ST-200, don't waste your time with that POS company anymore. I'm sure some Peterson fanboy will call me wrong, but I've gone down that road and bought them based on their hype and they just don't hold up like they should (especially for the price tag). Buy based on the quality, not the name of the brand. I will be buying Sonic Research tuners in the future instead.