op system upgrade?

alright guys

basically i keep hearing about this un official op system that everone is raving on about only had my mpc a few months, what am i missing out on and is it worth me upgrading and can i revert back to my origional settings easily enough if required?

sorry to be a bore i`m sure most of you know all about what i ask but i`m interested in gettin the best out of my gear

thanks

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