I don’t know which one to get so I need your help!!
I haven’t used a Supernova, but my friend has a Genesis,it plays really nice! Its smooth, it feels comfortable in your hands, it spins long, I have no cons about it! Thats just my 2 cents about the Genesis. Hope I helped a little. 
I have posted on numerous threads almost exactly like this one, please use the search bar for this thopic, you will find what you are looking for…Just look throught the help/recomendation section for something vs genesis, you will definitly find it.
can you give us something to go on??.. supernova is gunna be fast and stable, variable depending on which umm… size you get SN, SN lite, or Nova, and it will spin for a good long time, but the spin department of the genesis is gunna have the advantage, and it will also be more stable
I have both. I like the Supernova just a little better, because its faster. Both have long spin times, but the genesis probably would nudge the Supernova out in that category. You can’t go wrong either way.