Can anybody provide a brief pro/con list for each of these three mod managers? Is it possible/advisable to use more than one?

NexusModManager makes keeping mods updated much simpler; BAIN seemed to be the "new thing" after OBMM had been out for a couple years. Any constructive thoughts or advice is welcome.

http://www.gamesas.com/topic/1084204-bain-mod-installation-projects/ and only BAIN. Reasons in the thread.

The only added bonus to NMM is notifications when a mod is updated. But in doing this you miss out on many and much other features offered by BAIN.

Also this questions gets asked about 1-3 times a week and searching will give many answers.

BAIN definitively. There is no alternative to Wrye Bash, if you`re planning to build more complex mod setups. You can learn to use it from these excellent http://oblivion.nexusmods.com/downloads/file.php?id=35230 pretty fast.

OBMM is only needed for mods that make shader edits, like Nighteye Shader Replacement. I only have two of these mods, so I could make BAINs out of the edited shaders, getting rid of OBMM finally.

I think most mods for Oblivion won`t be updated anymore as most modders probably moved on to Skyrim. I`ve never tried NMM but the update notifications feature seems very useful nevertheless, especially if you`re using more than 100 mods like me.

Bain for sure... you can test mods safely... OBMM is good and all don't get me wrong.. but if you want a hardcoe setup.. you NEED Bain...

What others said, I fully agree.
But I'd also point out that you can use both: I use NMM for downloading mods into BASH installers folder, which makes keep tracking of new versions for installed mods easier.

In any case, NMM == OBMM for many purposes, so the exclusivity choice is NMM vs OBMM vs similars. => No need to have installed more than one of those.

Thank you all very much. I hadn't considered the option to have NMM save to the BASH installers folder. That's a great idea.

Even this isn't really a necessity anymore with the rise of OBGE. Mods that edit the vanilla shaders should all be considered obsolete at this point.

...Unless, that is, you don't WANT all of OBGE, you really just only want http://oblivion.nexusmods.com/downloads/file.php?id=7327 and/orhttp://oblivion.nexusmods.com/downloads/file.php?id=23372. That said, at this point I might just BAIN-up my edited Shaders folder and be done with it.

I`m using OBGE, but is it possible to implement mods like Nighteye Shader Replacement or what are you refering to?

Yes, that's how OBGE works. It bypasses the vanilla shaders and invokes use of its own versions. That's how Liquid Water pulls off what it does, and how the rest of them work. Getting the night eye shader in there would only be a matter of someone writing something up, and unless I'm mistaken, Sabel did just that with one of his SDR updates. Less blocky water reflections ought to be fairly simple for a shader person too. Then again, maybe not, or they just don't consider it important enough?