Hmm well I ordered got a DSE901 battery just in case.
It's a 3-piece which I have yet to try, so we'll see how it goes.
The prefilled juice in the 4081 Cartomizers burn out very easily compared to the KR808D-1 Cartomizers, its about 4:1 which is worrying. Perhaps the juice is too thin or they dont fill it up to max capacity.
If I fill the 4081 cartomizer with WOW juice, they last much much longer.
Both types of cartomizer look very similar internally, only the threads look different (beside one being male and the other female).
Perhaps someone here who is experienced with all types of batts and carts could post a sticky thread with the compatibility of all the brand and models, and what model battery each 'reseller' use.