What do you need from a direct box? The Samson seems okay by the reviews, but there are better ones out there. $50 is pretty cheap for a stereo DI.

I have this. Works fine. Battery life is a good few months (edit: when using it twice a week), although I now use it with phantom power.
Put phantom power on both channels, I'm convinced there's a noticable drop in headroom when only powering one (although it still works fine).