i purchased my first xm from someone who bought it as a snowcheck, and for whatever reason, he wanted to sell it right away. i wanted a 163 pull start, this one was a 154 e-start..........BUT the price was just too damn fine to turn down and i wanted a new xm chassis sled. to make a long story longer, later on i bought the 163 i always wanted. i couldnt get any more on trade for the e-start. i couldnt get any more selling it privately with e-start. so i figured "why should i pay more for it new from the dealer." so now i have a 163 pull start.
from a money's stand point, i dont think it is worth it. you will never get that initial investment back out. but i will say this....after having it for 1 season, then going back to pull start, I MISS IT. you dont notice it in the morning, or even the first couple hours of riding. but after you're whipped out from riding and/or digging out stuck sleds all day, the little yellow happy button is sure nice.
if you are undecided, another thing to think about is this.... how long do you keep your sled? is that 4th year of warranty going to make a difference to you? it wouldnt for me. i dont keep sleds that long. HOWEVER, does that extra year of warranty help out your resale? i say "yes". if you were buying a 3 year old used sled, would you pay more for e-start or more if you knew it had 1 more year of bumper to bumper warranty? i would say the warranty is worth more to the majority of buyers.
the financial part of it says pull start + 1 extra year of warranty. the convenience says e-start...its all personal preference. and if you're concerned about the weight of it, you had better be in perfect physical condition. because if you are not, the lose 15 lbs off your big *** and its a wash. dont take that personally, i have plenty more than 15 lbs to lose myself
behind seat battery - i too seen that in a video. while pricing out a sled on the doo web site, i was looking at accessories. if you want the "behind the seat bag" (not tunnel bag), it says you are required to purchase and install the battery box/tray on non-e-start models in order for the bag to fit. so i say yes, behind the seat must be where it is at. all the weight they claimed the dropped by going with the lighter starter, they probably gained back in power cables going back to the battery!!!