Wizard spirit question

Hello!
I have got feoh stormscreamer 94 lvl, shortly i think i reach 95. I still got Arcana power( from 3 rd) and with full buff i got ~ 80 k m attack. Because in 95 its possible enchanting WS i got some question to high lvl feoh - how much give its enchant?
+1 (time) give - 3 second or more, less?
Its worth replace Arcana Power ?
Now i focused on pve ....

Each +1 Time gives 1 sec, so +10 will be 40 sec.
Not SH but I would keep it until 99.
WS is a good combo with dual casting in pvp, but only with 99 version.

I kept arcane power until 99 then swapped it for wizard spirit.

Keeping arcane power was definitely the right thing to do.

Changing it at 99, I am still not convinced was a great idea, although wizard spirit is probably better for the olympiad.

With good gear, and wynn dual class and if you are planing to gear up your self with good gear i would keep AP. If you are going for olympiad wizard spirit will give you more benefit. But for mass pvp, party pvp i would keep arcana power.