Smoldering is overall better itemized for Holy, Sho'ravon for Shadow... but Sho is higher ilvl and has more stats, particularly Int so if you use Sho for Holy then you're going to want to reforge the Crit to Spirit
If you compare H Censer to H Kho+Goblet, after all enchants/gems the MH-OH combo has:
- only 4 more int (pretty much exactly the same on int)
- significantly more haste
- a little more SP
Censer has considerably more Spirit, with a slight loss to SP and haste. So, there's your deciding factor.
Leads me to believe that if you're OK on spirit/haste, Sho'ravon is actually top.
I would use Sho'ravon for both healing and shadow. Reforge mastery to haste for shadow or spirit for holy (probably, depends on the rest of your holy gear, you could just use the haste reforge for both specs). Ko'gun + Goblet would be the best non-heroic combo though.