I've ordered a 90D, and it will confirm on Sunday. But I've been reading that the 90kwh battery apparently degrades a bit faster than the 85 does. That's left me wondering if the 90 is worth the additional cost. How long can I expect to get the extra 14-15 mile range from the 90? How fast will it degrade to the equivalent 85? And is the degradation really a steeper curve than the 85? If so, how long before a 90 has less range than an equivalent-aged / used 85? Anybody done any data collection on this?