I have been using a Mechatronics 3 axis board for about 5 months. I have had nothing but problems with it from day 1. I was always losing steps and the motors were slow, 35-40 ipm. Finally, I couldn't slow down the Y axis enough to keep from losing steps and ruined 14 out of 35 pieces for a new customer. I replaced them so they won't even know, but that ate up a lot of my profit.
I had thought about Keling or Gecko drives from the start but didn't want to spend the money to replace a board that I thought was going to work out ok. Boy do I wish I would have done this a long time ago!
I installed the 540 yesterday, with a bit of help from Mariss, and did some testing today. Using the same 24volt power supply I have gone from 35-40 ipm to 130 ipm! I just finished running a pretty lengthy test, just a zig-zag pattern that exercises all three axes and this thing didn't miss a beat! I was cutting with a 90 degree V bit 1/8" into redwood at 100 ipm - it could have gone faster but I didn't notice that Vcarve Pro defaults to 100 ipm and it wasn't worth going back to change it and run again...
At just over $300 it's a bit pricey, but the time and money I have lost messing around with the other drive would have paid for the Gecko several times.
If you ask yourself if it's worth it to spend a bit more - the answer is absolutely YES!
Gary