Improves casting speed using Fast Casting skills?

I recently got this from a Collector post-searing near Ascalon City:

Inscribed Chakram
Energy +6 (req. 5 Fast Casting)
Improves Casting speed using Fast Casting skills (Chance: 20%)
Improves skill recharge using Fast Casting skills (Chance: 20%)

My question is: Does this actually help me out at all? As far as I can tell, there is only 1 (elite) fast casting skill, and by the time I get there, I'm sure to have something much nicer than +6 energy.

If it doesn't help me, then why would a collector be giving them out?

Thanks in advance

I also have a +7 energy off-hand item. Would that be better?

Use the +7 because the description is what it says. They added it because they probably weren't really paying attention to how useless it was nor did the probably care.