In topic, I personally love the Lucifer for how cool the throwing rose looks, and also that swordmaster skill where you clap your hands and the thorns spawn around you. I find it really hard to use it as a main weapon though, cause' I can't seem to be able to use some of it's combos properly in the middle of a fight. I use it more than the Gilgamesh for sure, but it's more like second choice for the Rebellion most of the time, and mostly using the swordmaster skills.
I suck so bad at using the Gilgamesh along with the other Arms. Usually for these enemies I choose the Yamato, since I found out it affects them in a similar way that Nero's Devil Bringer, while being much faster and safe than the Gilgamesh.
Just charge is awesome though.