acts_as_taggable -- which one?

There appear to be three acts_as_taggable implementations and I'm looking for
a recommendation on which to use.

- Gem
- DHH plugin
- Dema mixin

The Gem implementation appears to be obsolescent, from what I can read on
the lists and Google search.

I like that the DHH plugin uses polymorphic associations because there will
be lots of different taggable items in my application; however, adding and
removing tags is a bolt-on, not designed-in feature.

The Dema mixin
appears to do more right out of the chutes but is HABTM so it may not be as
flexible as DHH's.

Does anyone have thoughts on which has been most productive for you? How
about the add/remove tag features?