I like the KR808D-1 cartomizer for convenience, but I also like to direct drip. I ordered some 901 attys so I could direct drip on my Vapor4Life
batteries, but I got impatient and ended up cutting a Greencig cart in half to drip. Wow.
The Greencig cart has an atty made of fiber glass hairs, the hairs hold about
three drops direct drip perfectly. Because of the way the hairs are tied directly to the heating coil there is no area underneath the atty where fluid pools and flavors mix (as with most metal mesh attys) so you can change flavors every time without cleaning the atty.
The Greencig cart yields clouds of vapor on a V4L auto passthru (doesn't work with the V4L manuals, so watch out for that gotcha - you have to use an auto), and the design of the atty seems to keep going and going and have a long long life to boot. Plus you don't have to use a ton of fluid as with the larger attys on the large hybrids.
Anyone who tries this, note that the Greencig carts are made of a soft metal so they cut easily, and you can slip a V4L rubber "condom" or two over the Greencig cart (after cutting the sealed end off) for a nice feel and insulation from heating the chamber.
I'm sure you'll get a million opinions, but I haven't found a direct drip atty that is more convenient and consistent then an open Greencig cartomizer.