Engineering trinket vs wintergrasp trinket

What would be more usefull... atm I'm farming for engeneer 425 -> lightning capitator, use ~3k dmg 1 min cd & casting while running, ~1,5 sek casttime right?
otherwise new wintergrasp trinket: use +440 dmg, so I'm gonna use both wintergrasp spelldmg trinkets for pvp, but i think the capitator would be more usefull in arena ... but then I loose about 80+ resilience and spelldmg
ahh fuck I don't know :<

Do you know if the trinket work in arena and whats the range?

eningeering trinket is better. 1 second cast time, 30 yard range and it's not tied to the gcd.

and you do not think they're gonna nerv it like rocket boots in s3?