Something else to keep in mind..
So far, the secondary market for electric bikes has been very soft. You've probably seen some people selling Enertias here with very few miles on them for 50% off sticker.
I think this has a few reasons:
1. EV buyer pool is very small. Will have to see if the big-battery electrics (ZF6/9 and Empulse) attract more interest.
2. Technology is advancing very fast; a 3 year old Enertia or 2010 Zero S has been leapfrogged. If J1772 picks up any kind of penetration in the next 2-3 years then the lack of a J1772 plug will stick out.
3. Uncertainty over battery life, buying used / without a warranty is a somewhat risky endeavor.
4. I suppose that most EV buyers today are very interested in pushing EV technology forward and voting with their wallets. Buying a secondhand EV doesn't directly advance EV technology.
5. Market value for the small EV bikes, even new, is still significantly below what Brammo and Zero were selling them for, which is partly why they had relatively few sales. The sale values of the nearly-new bikes on the secondary market is a more accurate valuation.
With all that said:
If someone in 2014 is ditching their nearly-new 2013 Empulse for whatever the new hotness is and is willing to take a 50% haircut, I'll be first in line to snag it. And I think it would be a long line. I would think the Empulse will hold its value a bit better.
The reaction to the Enertia et al is largely "meh" .. and a 50% price drop for a nearly-new bike doesn't seem to have moved it much.
The reaction to the Empulse / 2012 Zeros seems to be more along the lines of "wow, that's expensive.. but I'm interested now." Used bikes may see quite a bit more interest.
