Mage on T7 PvE

[Juampe77]

Hey all! I want to ask you if mage is good on this patch on PvE, and if you recommend me rolling one. I love the class but I always played it on ICC with endgame gear, and as far as I know, on Naxx/OS/EoE content you should play Arcane. Although, question is: is it really viable? How much haste should I have? And can I get that number with pre-raid BiS gear to do decent dps on my first raid? Without knowing, I assume you have to be full haste gems and enchants to get there.
Ty in advance for your attention!

[Foune]

Both arc and fire is very viable, fire problably more so because of crit gear in naxx.