What is the opinion of Reddit about the
Thumb Keyboard (Phone/Tablet)?

I checked and it is cheaper via amazon than the market place:
1.29 versus 2.29
http://www.amazon.com/Beansoft-Thumb-Keyboard/dp/B004X71YY2
https://market.android.com/details?id=com.beansoft.keyboardplus&hl=en

It looks like this keyboard, which is free for just today: http://www.amazon.com/gp/product/B004X71YY2?ie=UTF8&ref=mas_faad