I wouldn't dare step on the arenas with that combination of eternal resolve glyph+soul link. it's the same as serving my head on a silver plate for all classes with interrupts and mild bursts, that can literally keep you stunned/silenced/school locked/overall vegetative while they zerg your life. Oh Hi Rogues, didn't see you sneaking on my back.
www.euwowgold.fr
I do admit that most shadow priests that I've faced in PVP are way less threatening than they were in the beginning of MoP, but that is more related to all the other nerfs to their utilities and instant casts than their 'survivability' and passive reductions.