I just bought the Zenbot. It came in a couple of days ago and appears to be a good machine. I have not cut anything with it yet though. The biggest thing to consider with that one is that it is tiny. The other two machines you listed are larger. I can't speak for them since I don't own them. The only thing about #2 that strikes me is how you plan to hold your work down on the table. With a smooth surface like that, you may end up drilling some holes in it first. You might want to ask that guy what the hold-down setup should be (carpet tape perhaps???). I do like a moving table design though. Implementation is key. It can be a great design, but if the guy is a sloppy builder, it all goes to crap. That is kinda the risk you run in buying something from ebay. The first machine I bought via ebay looked good in the ad, but when I got it, I found out it was built crappy and didn't perform well. My new Zenbot looks good so far, but I have not put it through it's paces yet.