Gen7 with Wantai driver board?

Starting to make my shopping list and I was a couple steppers short so I hopped on Ebay and found this setup. Basically it's a 4-axis driver board, 4 78oz-in steppers and a 200W power supply. I thought "heck, that might be useful." I plan on etching my own Gen7 board, but I thought getting a commercially available driver board might be another solution to making my own, especially if it comes with new steppers and PSU. (I don't really need all that, but maybe somebody else does.) Am I wrong in thinking the driver board simply takes a signal from the main board and essentially amplifies it? So, basically any driver board can be run by an Arduino or Atmel?

What would be a good minimum torque motor? I have a couple 70 oz-in and I think a 60 (maybe smaller) and a couple old desktop printers still waiting for dis-assembly.

Several years ago I built a CNC machine and I tested it with Mach3 and a 3-axis driver board from EasyCNC (IIRC). It ran great but I was too busy to devote time to learning how to convert my shapes to G-code and tool paths so I sold it. But I've always wanted to get into rapid prototyping and CNC milling, maybe now's the time.

The driver board you link is designed to work with a parallel port, so you would need to use one of the free cnc programs rather than using pronterface or one of the other reprap software solutions. It would likely be more work, especially the extruder, but I think it's been done( like seemecnc.com). You are likely to have an easier time using a USB-serial based electronics because it will work with the standard reprap firmwares and softwares out there, but it might be worth a try if you really like the price.

Thanks bryanandaimee,

I'll be making a gen7 board and, from everything I've read so far, I won't need an external driver board. I thought it might be an option for somebody, but it sounds like it would be a lot of extra work to get it to work properly.