I do 100% with a drop tank, always. Heck, if I could attach a fuel truck and drag it around at 17k I would. I run out of fuel before I run out of ammo most times. The 190A5 has 500 rounds of 20mm, which when used in bursts goes a long, long way.
The trick is patience and E management. The 190 series is excellent for several high speed passes then you need to start thinking about egress and reset. I fly the A5 because if and when I get into a low alt, low speed turn fight it is the best turner of the 190s. Contrary to popular opinion it is pretty good down in the weeds, if you know the limits. I've killed plenty of PonyDs, Jugs, 38s, etc in the weeds. Even in the hands of a noob the turner birds are a bit much for the A5 in the weeds.
In any case, as Pervert told me many moons ago, if you want to excell in the 190 (he was speaking of the Dora) prepare to die a few thousand times before it all makes sense.
Boo