In the original thread for a diamondback sorrento I ended up getting a great crank and chainrings built for a much better specialized rockhopper(no creaks, wider gear range). that worked good but the front derailler would rub on the outside cross gears and being acera X was kinda cheapy. So I bought and installed a Deore derailler for $26. It's great. Shifting is flawless and I get no chain rub even in the far cross gears. I like it so much I may put a Deore on the rear just to make it match. Then maybe we'll have a look at that cheapy stem and headset.