Switching out JUST the battery to lithium ALONE on my SW was 10-11-pounds. And now I learn I can get rid of the battery box (3-lbs) and the solenoid (maybe a pound with cables) and of course the starter--likely 7-8 pounds--so: 25 pounds. And not ONE trail will get closed because of it.
Plus--and NOT being a smart-ass here: I lift weights and coach people on this for a living. Since I do pull-ups with 60-pounds attached to my body--I can handle 6-10 more reps of right arm pulls per daily ride.

I have owned 8 sleds--Never had E/S--and never will. Even my girlfriend has to "suck-it-up-buttercup" and pull start her (my) Indy 800 SP. I do the honore when cold. This will be my second sled where I removed it. No regrets.
Then I have my Bikeman pipe waiting (5-6 pounds) and trail-legal can (13 pounds) so THAT adds up to a LOT--ALL off the front. Wheelies for days.....
Note: If I can remove ALL of the E-start--I will sell it for about 40-50% off list ($350). And that is my PCV cost.
I do this weight-weenie stuff with everything: Mountain bikes; Motorcycles; Snowmobiles; And clients....
AS Colin Chapman of Lotus automobile racing fame said: "Making more power makes you faster in a straight line. Making a car (snowmobile) lighter makes you faster EVERYWHERE--acceleration; braking; cornering. ADD: Lightness".