I'm thinking you use mostly cleaner fruit types? I like the 'sticky' ones such as custard, cream, toffee, chocolate, etc.
Two that I've been using in mine are the Kilo White range in either Chocolate Ice cream Sandwich or White Chocolate Strawberry. Not as bad as MCV, but don't last as long as yours has.
I use MCV in an Evod, and the coils are fairly cheap, so I don't mind changing it every 3-4 days.
I do like the Nautilus2 though ...just wish it held more!
I had a problem a few days ago - just filled it with the strawberry cream one and the coil gave up with very little warning ...and all the strawberry cream drained out of the bottom like a sink emptying!