I play a full vit end game Priest. Tho I do switch from full vit to full psy often as I like to deal dmg with my priest in pve. Full vit works and heals are still decent with +ed Aquas and or psy/ vit twins. Or even feathers.
My priest uses 2 +15 I/P/V rings and two vit twins and heals just fine.
I'm not home right now and won't be until tomorrow so I cant show you my skill build until then.
Maybe someone else can in the meantime.