Gary,
I went with the passive reso pickup. I didn't like the idea of having to open up the guitar to change batteries. Also if you go with an external pre-amp, you can opt for one with volume and tone controls which is kind of handy.
However, before investing in a preamp, try playing without one. I play mine through a Marshall acoustic amp. It has an adjustment to compensate for the low output of the pickup and boosts the signal enough so I don't need a separate preamp.
Erv[This message was edited by Erv Niehaus on 18 May 2005 at 08:18 AM.]