I think for most riders it's totally a personal preference thing. I like the simplicity and weight savings of going without, but then I ride a 600 that definitely doesn't need any extra weight, and is easy as pie to start unless it's dead cold. For a power user spending thousand$ on lightweight parts, it doesn't make much sense unless they need it. If you need it (bad shoulder or whatnot), then you need it. Of course, most riders (including myself, at least at this point) might not even notice the weight difference in a blind test.
I'd look at it like this: on the one hand, if starting a sled has never bothered you, then why spend money and add weight with ES? On the other hand, if you want it, you'll probably notice the convenience more than the extra weight.