A few games ago, I was playing Maokai, and I found myself constantly out of mana and also clearing camps very slowly if not digging through my sparce mana resource. ( I was very behind that game)
I already bought Ancient Golem and I thought by myself: "Damn, I could really use a Spirit of the Spectral Wraith right now to speed up my clear a bit and give me more mana regen." And then I thought: "Why the heck not?"
So I tried it out and it worked extremely well, also in games after that were I wasn't so behind. These items are just so cost effective and give so ridiculously awesome stats for a jungler that I think it's worth paying for the non stacking butcher passive.
here are some champs I combine jungle items on:
Maokai: SotAG and SotSS
Amumu: SotAG and SotSS
Skarner: SotAG and SotEL
Evelynn: SotEL and (sometimes) SotSS
Nunu: SotAG and SotSS
Galio (yes I jungle Galio): SotAG and SotSS
Blitzcrank (yes I jungle Blitz too) SotAG and (sometimes) SotEL
If you know anymore champs I should try this on aswell or if you think I shouldn't do this, please tell me in the comments!