Which rechargeable battery you prefer for the HP-41?

[rprosperi]

N cell NiMH batteries I've used w/o problems for several years are still available in USA/Canada from Interstate Batteries, however they cannot be purchased online, they have to be ordered through your local IB store, and paid/picked-up there. I assume this is a result of the general fear and loathing of mailing batteries, even though this does not apply to NiMH, but could not get an answer as to why no online sales.

Spec: 1.2V 500MAH NIMH N CELL
Part number: ASC1055
Price: $3.90/ea. in qtys. of 20 (but possibly the same even in low qty.)

Not cheap, but good quality, reliable, and above average capacity.

Here is a list of the Interstate Battery store locations, there are a lot more than I expected.