Review on Iverntech MGN12H Linear Rail Guide With Stainless Steel Carriage Blocks - 700Mm Length For 3D Printer And CNC Machine by Garrett Flores

Now Im not a machinist, but i think some people expect professional grade machining from low end parts. Not to say there is not legitimate criticism in these reviews. Rust? Unacceptable. Slight drag? Acceptable. I bought 4 of these, a pair at a time. First, love the look of the black, keeps the glare from light shining off them and onto my computer screen to a minimum. I also bought a spare set of ball bearings and some new oil. First set, drag on both, not terrible but i followed the advice of other reviews, cleaned with IPA and re-oiled. Came out acceptable. Second pair perfect out of box, im not going to even bother cleaning or reoiling. For the price, im happy. They perform as expected.