I've switch from rbenv to chruby[1] years ago. Seems simpler and doesn't have the rehash command that is (was?) required with rbenv. All it does it adjust your PATH.
Personally I swapped from rbenv to asdf a while back. I don't think there's any real justification for one over another these days, just use the one you're comfortable with :D
Happy asdf user here. If you're only using ruby, then asdf isn't much better or worse - but asdf is great for supporting other toolchain, like python, crystal, rust, go... AFAIK the asdf ruby plug-in uses rbenv under the hood.
rbenv handles only ruby versions, whereas rvm also handles gem installations. I think it's simpler when you let rbenv handle ruby versions and bundler handle the gems, because you have to deal with bundler anyway.
