They both have limited use but can be handy for some jobs. *For $20,
I'd try the new one.

the new one will probably have Lithium-ion batteries,and will hold a charge
while in storage,for about 6 months.

while the NiMH(gold) and NiCd(silver) both self-discharge in storage.

This doesn't leave me much of an answer. Does this mean I should keep
the 9078 and get rid of the Versapak? One advantage to the versapak is
that you can charge one battery while you use another. You can't do
this with the 9078.

Speaking of which, how long does the 9078's battery last compared to
the Versapak Gold battery? Plus, the 9078 is more compact than the
Versapak, which is more clunky. But still, does that make getting the
9078 worth it??

I'd appreciate more info to know if it's worth even getting a new
tool.

-Joel