I grabbed one of these Pololu boards for testing and was pleasantly surprised with what I found.
They are tiny, quiet, and capable of taking 1/16th of a step. This means I will be able to multiply the resolutions of my steppers by 16. With a higher resolution obtained through micro-stepping the print quality will increase. That's all well and good, but the real reason I'm going with the Pololu / Mega option is because I really believe this type of solution is the future of Reprap tech. I can't really put a finger on why I feel this way.
So, I think it's time for me to dust off my mill, pull out some double sided PCB, and make a mega shield. Now that just sounds cool!