Given the current state of development for Wrye Bash and TES5Edit, which is the most effective and stable patch option; TES5Edit's Merged Patch or Wrye Bash's Bashed Patch? I'm assuming one wouldn't want to run both.

to my knowledge the TES5Edit merge patch is not functional atm.

EDIT:

I should add that they do entirely different things and that it's beneficial to use both.

The two definitely are for different purposes.

The merging Bash does is very selective and has a lot of requirements, and that's because the "merging" it does allows you to run plugins as if they were actually installed, without creating a merged plugin. This is important for your saved game, since all FormIDs will stay the same using this method. This allows for changing of your Load Order and re-merging (via the Bashed Patch) without having to do a clean save.

TES5Edit merging is different. It can handle a whole lot more, and doesn't have as many requirements. But that's because it's more designed to ram two plugins together into a new one, rather than ram 2 plugins into one and still have them behave as if you had the original mod (as far as FormIDs go).

TES5Edit also can do some other nifty things of course, but you have to understand what each is used for and when you want to use them.