Just an FYI on the 401 E2's: I've been trying out some of the early ceramic (standard length) M-series on 401
batteries. Mine measure 2.5-2.6 ohms and I find them a little harsh for my taste. I notice Turbo said he thought the 3 ohm were a little cool, so since they offer a 2.6-2.8 ohm model that might be the sweet spot for these. Hopefully some of the suppliers over here will start carrying that version, but in the meantime you can get them direct (if you want 100 of them).