First off, what kind of runtimes can I expect using 3000 6-cell batts?

I have a bunch leftover from my old touring car days, so that's whay I'll most likely use

How exactly does the switching on the lockers work?

The site says there are 3 options (Unlocked, Front Lock and Front/Rear Lock), but going by the video, it looks like an SPST switch that just locks both Front and Rear

Also, what kind of range will I get out of the stock radio system?

I've been looking for a basher that will go just about anywhere and not get stuck (like a crawler), but sumthin fast enough to get out to its own way if needed

This seems to fit the bill nicely