What is the best cube for cutting corners and that has speed. (Hybrid is fine)

[Musturd]

My edison can make amazing cuts on even a really tight tension and its pretty fast after broken in.

Agree'd.
Before lubrication, my Edison was faster than all of my other lubricated cubes. After post-lubrication, it's even better.
It also cuts corners excellently.

BUT, I keep my tension very very loose. If you turn it any further than its maximum corner-cutting angle, it will pop.