I just received the MaxX Fusion Mini Kit and am quite impressed. It is very different from the 510 in that it is a two-piece, cartomizer-based Kr8 model. My
comparative review* of the Kr8 and 510 will give you some idea of the differences and pros and cons, although I do think that the MaxX Fusion transcends the other Kr8s, e.g., far superior vapor. The "mini" (65mm) battery that I received results in a Super-mini (i.e., analog-sized) e-cig. The "standard" (78mm) battery yields a Mini e-cig: the same as other Kr8s and slightly longer than the 510.
* NOTE: The
updated version of that review substitutes the eGO (and similar 510-based fat batts) for the basic 510 e-cig. If you like the 510 atomizer, but got tired of frequently charging
batteries, I urge you to give strong consideration to this option as well. And my
eGOs and Rivas, Hellos, Oh My! article describes these fat batts in much greater depth.