A genny would arguably be the best to use with mesh. Taste/flavor is also oft used as a selling point of gennies, but I think a properly built rda blows the gennies I have used away (nextgen, steam turbine, Oz22, Nahulon)
Mesh is clean tasting, if a bit harder to get right, but I really dont mind the taste of cotton, just my opinion and everybody has one of those 8)