It depends on the type of driving. In stop & go city driving, regen saves wear on the brakes and does improve range. In highway driving it can be useless or worse.
Brilliant Silver 2021 Leaf SV40 W/ Pro Pilot & Protection
2009 Vectrix VX-1 W/18 Leaf modules, & 2 lithium E-bicycles.
BAFX OBDII Dongle
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.