While I am busy getting all the detail into the CAD and making sure all the dimensions are correct, a question came up, that I want to ask the collective of experience in this forum.

This question is, if I can use the chinese linear rails (like these), or if there are any known problems with their accuracy or surface finish that makes them bad alternatives? I am asking this, because of just how much cheaper they are to get. Same question goes for the ballscrews.