Hi Hanermo2. Thank you for your input, I will consider an MPG - it sounds like a nice feature. But you are way out my league. I am building this machine because I cannot afford to buy a similar machine (and because I think it is fun). Obviously for professionals and companies a difference of a few hundred € per axis is no big deal, but for for my little private project it makes a difference. Also buying one or three MPG's makes a difference.