I've recently built up a pretty full-range Tile Tracker kit, and I have to say, after some teething its a really cool piece of kit. Deffo worth it if doing a wet-room (as I was) what a shame to batten screw through my schluter Kerdi!!!
The lip on the top of the solid ally rail is a bit annoying though, I usually build out the height with spacers so the tiles sit just above this....it can't cope with lumpy/bumpy walls otherwise!