mage gears question?

[ujangkampak]

Hell-oh. Okey i have some question.
mainly im just playing Pve.
Im just confused to choose some gears..
1. Immo staff or immo gun?
curently i using imo staff, but sometime i runing elites glinstone / underhull with any mages using immo gun, they can killing fast and of course the proc is cool. Haha lol
So which is better?
2. Planar pendant or Cryo heart?
Curently i using planar pendant. When im compare the stats with cryo heart lv54 in cs. I lost about 300+ hp and add around 25 dmg ( display compares with pp hidden bonus ) and get some crit.
But im looking around, some carzy mages using cryo.
So which is better?

My current gears?
Immo staff
Antignome helm
Antignome armor
Mythic belt lv56 ( forgot the name lol )
Arc ring
Planar pendant

Any suggestion are welcome
Thank you.

Regard
-S