I may be going at this completely wrong, but to be fair I think total puffs/draws before recharge is the better standard to go by rather than hour avgs.
Avg DSE901 I'm finding 180mah battery capacity with everything from 150-200 puffs/draws. Lets just say you'll get 180 puffs out of it before you have to recharge and at 16 puffs/cig you'll get a little over 11 analogs out of it. And as the battery winds down the last couple of cigs aren't all that good.
For the 401 I'm finding 200mah capacity. With 200 puffs before recharge you get 12.5 smokes per charge. And at least from what I'm experiencing the last puff is as good as the first, then nothing.
So you get a much smaller package in the 401 that lasts only slightly longer but performs consistently throughout. Conceivably a half pack a day smoker could go all day with one 401 battery while a 2pk a day smoker is going to burn through 4. Anyone want to count their puffs.
That's why I want a charging case like the PCC for the Dura. I'd just like for it to accommodate 2 complete 401s and a place for a couple extra carts or slim juice bottle. You would be ready for a whole day out, battery always charged, even a spare atomizer, with nothing more than an analog sized pack.
Sorry, it's late and I could be completely off on the battery issue. Guess I'll unplug the passthrough and head off to dream about a PCC for my pilot to free me from the charger.