Now that I have my shiny new keyboard to play with, I was able to try different pads I have to see if any of them would work. And as it turns out, the sample OnPurple pads I received with my - AWESOME - purple pillow work great! I have larger hands and I was constantly hitting the fn keys and this took care of it and I find that my typing accuracy has improved significantly… I only had to use the backspace a couple of times on this :0) TheOnPurple pads are 2.5" square, and roughly 1/2" thick. I think something that is between a quarter to 3/8" would be perfect for me