for batteries if these hyperion 6000s give up the ghost the ones from promatch are prices reasonably and have a nice warranty on them.
For ESC, went speed passion GT2.0 after the MMP couldn't handle it without mods. Not a real knock on the MMPs, they just don't have the BEC designed for this stuff (loved it in 1/8 e buggy usage, no mods). the Speed Passion GT2.0 Pro for the money has no issues in 4x4 sct.