I used a Gomadic (not the one linked, an older model) for many years with my 305. Did the job well. I would remark though that they aren't the most robust bit of kit ever made, mine eventually died on the road during PBP. I'd imagine prolonged road vibrations etc saw it off. That said, it had a good run and they are cheap enough to be considered disposable.
Edit: a point to note, some of the original Gomadic's didn't take rechargeables, std alkalines yes but not rechargeables. Rechargeables are (or were perhaps) ever so slightly bigger and wouldn't fit properly inside the unit. I don't know if that is true of the newer models though.
Edit: a point to note, some of the original Gomadic's didn't take rechargeables, std alkalines yes but not rechargeables. Rechargeables are (or were perhaps) ever so slightly bigger and wouldn't fit properly inside the unit. I don't know if that is true of the newer models though.