Get the Touchstone.
I got one for each of my Touchpads (32G & 16G) and have only had them connected to USB a few times for messing with some files.
It's just so convenient to park it on the Touchstone whenever you're not using it and having it be at 100% all of the time. I have a leather case for my 32G TP and it charges right through it with no trouble at all.
Do be aware that unless you can find a used one you're not going to get any deals. They can be found, but I gave up trying to nickel and dime on them and ended up paying between $40 and $60 shipped. I suspect the people who have them realize there is a slight demand for them even though TPs have essentially disappeared...