Could you guys help me out with this? I started with V4L, so have KR808 cartos, etc. How do they work with these mods? I can't figure out how the juice gets into the carto. I had come to the conclusion that they must only work with "510" stuff, yet Jaguar and others seem to have transitioned quickly to these bottom fed mods. Does your old KR808 paraphanalia work with, say, a REO, or do you have to get all new stuff? I swear I've read these threads and gone to the manufacturer's sites trying to parse this out, but am still confused. Thanks.
I do not have an adapter for my KR8, I ordered a 510 atty & drip tip for my mod and use that. I haven't tried using a carto so I don't know how that would work. That being said, the 510 dripping either from above or below seems to give me better flavor and vapor than the cartos, YMMV.
I am planning to get an adapter to use my cartos just to try different things, and make switching flavors easier. With the atty, you should clean it when changing flavors, or just have one for tobacco flavors, one for coffee flavors, and one for candy/fruity/sweet flavors. I put some caramel candy on my 555 atty and yuck, took forever to get the flavor right even after rinsing it out with hot water.

Good luck which ever way you go, it's the little things that make life great.
Cheers, Jag