Review on Enhanced Ender 3 Linear Rail Guide Kit With Stainless Steel MGN12C Carriage Block And Slider For 3D Printers - Compatible With Creality Ender 3/Pro/V2 (300Mm, C-Type) by Rick Howlett

At first glance appears to be good for the money, but there were issues. The replacement mounting plate is off by a few thousanths, which is just enough that a Bondtech DDX extruder will not fit onto it without modification. Had to oversize the holes in the Bondtech by a few thousanths each to make it fit properly. Also, the skies for the timing belt are set too far towards the center and the timing belt wouldn't fit with the stock tensioner attached. Had to get a hacksaw out and cut two new slots a little further out on the bracket so the belts would slide in. Overall, not terrible for the price, but be prepared to do a few modifications to make it work