I finally took the plunge and got a Castle Mamba X w/ a 2850kv sensored brushless motor (2280kv was on backorder).

Setting it up was pretty standard for a brushless upgrade, but it took some time for me to solder together a y-harness for the AUX cable to work (if anyone has any tips on how to easily solder one, I'd love to know for the next time!).

I also picked up a field programmer and bluetooth module (not yet Android ready).

Took it out on its maiden voyage yesterday and wow and I impressed. It's super quiet, has really great low-speed control, can go faster than stock, and allows for some pretty awesome ESC-based control.

Battery run times were phenomenal (my son went through nearly 3, 5000mah packs while I still had plenty of juice left in the second one) and I was running NiMH!

The bluetooth link is pretty handy and it allowed me to make some fine adjustments on the fly - although, last night something went wrong and I had to basically reset the ESC to stock because it seems something became corrupt when i was updating the settings via bluetooth (after already doing it like a dozen times).

One trouble I did have was fitting all of the extra cables into the tiny receiver box - I may need to get a bigger box meant for another truck for this to work out better.