The Luna Cycle 54T sprocket for my Sur Ron X has made a notable difference in performance. It has not transformed the bike into a wheelie machine, as some folks have noted about the 60T version. But there is a good deal more pep and improved climbing ability. I live in a relatively mountainous area and was finding the stock 48T underwhelming on select hills. The 54T seems just right. (Still want more Power! Need ElectricRT battery and controller mod). Who knows, maybe I’ll also get the 60T. It’s such a fun bike and the sprockets change the feel, making it even more fun. I should also note, the sprocket seems well made and durable. Install was fine, but IF you have the Sur Ron X, you will need a new 120 link 420 o-ring chain, cut down to the appropriate size. The links included by Luna only work with the Sur Ron MX (non sealed/no o-ring chain). A chain breaker tool is therefore handy for the install. Thanks Luna!