This is cube is very easy to overlube. There is a lot less contact between pieces in the core than in most other cubes, so I wouldn't put more than 2 drops into it. I use lunar, and 2 drops is good, the cube still feels fast.
I tried 6 drops of lunar, and after breaking in the cube felt extremely sluggish, wouldn't snap to the corners (from magnets) anymore, and just wasn't fun. I wiped out all the lube I could, added just a single additional drop of lunar, and the cube is like new again! :)
I use the settings 2/5 (inner/outer ring), 2 on the corner magnets, and 1 on the inner magnets.
The cube is still a little loose, but it rarely jams where other cubes might jam because of the elasticity. While I'd prefer it a little more held together, I like the overall performance of the cube best on these settings.
Overall great cube!