Before the trip to Alabama started on this, used the trip down and the first day here to complete it. This test was done with nuport wow 36mg all from the same batch (17102011) on 3 cartos from each ohm/coil type. No cleaning was done, just ran them to the point they would no longer fire. These were all run on king diamond manuals, though after this info will have some additional notes not on those batts. Used a 6ml tank only holds 4.5ml's of juice, the carto holds the other 1.5ml to do this test, the tank is marked at every .5ml's, and filled it every time to the 5.5ml line. 
1.5ohm DC carto-
Carto A- Actual ohms (AO) 1.4ohms, amount of of juice before failure (AJF) 72ml's.
Carto B- AO 1.5ohms, AJF 66.5ml's
Carto C- AO 1.4ohms, AJF 69ml's
2.0ohm DC carto-
Carto A- AO 2.1ohms, AJF 67ml's
Carto B- AO 1.9ohms, AJF 71ml's
Carto C- AO 1.9ohms, AJF 66ml's
As we can see the dual coil cartos last a good 10-12 refills before failure. It's what was expected, have never had much success cleaning them, but the lifespan on them balances this out. Used a carto of each on an umentioinable at higher voltage. Again using nuport wow 36mg same batch-
1.5ohm dc at 4.7v- 58ml's
1.9ohm dc at 5.4v- 53ml's
As we can see the higher voltage will wear them out earlier, have other unofficial tests that shows it, those are estimated used though so won't post them.
Now for the single coils.
2.0ohm single coil-
Carto A- AO 1.8ohms, AJF 26ml's
Carto B- AO 2.1ohms, AJF 38ml's
Carto C- AO 2.0ohms, AJF 21ml's
3.0ohm single coil-
Carto A- AO 2.8ohms, AJF 31ml's
Carto B- AO 3.1ohms, AJF 24ml's
Carto C- AO 2.9ohms, AJF 19ml's
As we can see a lot less time before failure, but that's only half the story. First off these can be cleaned 2-3 times before needing to be tossed (no way to really dry them well yet, if there was sure could get more uses), and the story changes at higher voltage.
1.9ohm sc at 6V- 56ml's
3.1ohm sc at 6v- 57ml's
If you're using the tanks on a king diamond/stealth (vt or not) batt or the 808ego suggest going with the dual coils. If you're using the pt, a mod, or something higher voltage, singles get far closer the same throughput of juice as the dc's. Hope this helps.
1.5ohm DC carto-
Carto A- Actual ohms (AO) 1.4ohms, amount of of juice before failure (AJF) 72ml's.
Carto B- AO 1.5ohms, AJF 66.5ml's
Carto C- AO 1.4ohms, AJF 69ml's
2.0ohm DC carto-
Carto A- AO 2.1ohms, AJF 67ml's
Carto B- AO 1.9ohms, AJF 71ml's
Carto C- AO 1.9ohms, AJF 66ml's
As we can see the dual coil cartos last a good 10-12 refills before failure. It's what was expected, have never had much success cleaning them, but the lifespan on them balances this out. Used a carto of each on an umentioinable at higher voltage. Again using nuport wow 36mg same batch-
1.5ohm dc at 4.7v- 58ml's
1.9ohm dc at 5.4v- 53ml's
As we can see the higher voltage will wear them out earlier, have other unofficial tests that shows it, those are estimated used though so won't post them.
Now for the single coils.
2.0ohm single coil-
Carto A- AO 1.8ohms, AJF 26ml's
Carto B- AO 2.1ohms, AJF 38ml's
Carto C- AO 2.0ohms, AJF 21ml's
3.0ohm single coil-
Carto A- AO 2.8ohms, AJF 31ml's
Carto B- AO 3.1ohms, AJF 24ml's
Carto C- AO 2.9ohms, AJF 19ml's
As we can see a lot less time before failure, but that's only half the story. First off these can be cleaned 2-3 times before needing to be tossed (no way to really dry them well yet, if there was sure could get more uses), and the story changes at higher voltage.
1.9ohm sc at 6V- 56ml's
3.1ohm sc at 6v- 57ml's
If you're using the tanks on a king diamond/stealth (vt or not) batt or the 808ego suggest going with the dual coils. If you're using the pt, a mod, or something higher voltage, singles get far closer the same throughput of juice as the dc's. Hope this helps.