I'm not a big fan of the Solsylva machines. There are a lot of build threads for it at CNc Zone, but it seems like most people that build it, go on to build a better second machine. Not sure what your budget is, but the Joes 2006 machine is a much sturdier design.
www.joescnc.comI actually have a Xylotex on my 30"x45" travel router with 250 oz PacSci steppers. With 1/2-8 2start acme screws, I can get ~175ipm rapids, and have taken shallow cuts at up to 150ipm. Still fine tuning and setting it up, so haven't tried heavier cuts yet. With the Gecko G540 and 1/2-10 5 start screws, I've seen people at CNC Zone get 300-400ipm rapid speeds. I bought the Xylotex 5 years ago, when it was pretty much the only low cost option available. It works remarkably well, with one exception. On my router, I got resonance that was so bad the machine was nearly unuseable. I solved it by making dampers for the steppers. The Gecko has resonance compensation built in, so probably wouldn't suffer from the issues I had with the Xylotex.