0/55/16 and glyph of corruption questions

[allenwhoa]

first question: with a demo/destro fire-specific build is glyph of corruption worth the global cooldown for a shadowbolt? or would a different glyph be more beneficial?

second question: i'm currently 0/40/31 because i personally don't like managing the felguard. but that's beside the point, i know felguard can out dps the imp blah blah. anyways the question is, does anyone know if a spec like http://www.wowhead.com/?talent=IZ0xIzsgMq0sguAoE00q would completely destroy my current build's personal dps? i know it's more of a raid-support build but will my personal dps drop significantly? with this build i would use the felguard as i find fel synergy and big help to felguard survival

in other words:

improved immolate, devastation, and emberstorm

vs

using felguard w/improved demonic tactics, demonic empathy, demonic pact, and metamorphosis

please, no sarcasm, just need some tips. thanks for all your time and help in advance

*edited for 0/55/16 to be shadow based, not fire

[Offsprngr]

I currently have the demo warlock in the guild specced:

http://www.wowhead.com/?talent=IZbhIzsgMq0sguAoE0oV

He uses CoA, corr, immo, shadow bolt spam.
As far as I know he's using felguard, SB and corr glyphs. Granted he ought to change to immo glyph since it's incredible dps boost versus all other glyphs.

[allenwhoa]

thank you very much offsprngr. any chance for an armory link? it'd be nice to check out the gear status i'd need to be at to pull off that spec. how is his dps btw?

[Offsprngr]

http://eu.wowarmory.com/character-sh...nor&n=Ninjarou

He's been offline a while though, school exams etc.

[allenwhoa]

understandable thank you very much for your responses. it's much help and it's much appreciated