My understanding is whipper is more paranoid than abcde. whipper does a couple things to ensure a perfect rip:

* Rips tracks twice and ensures the checksums match (retrying if they do not)

* Compares the track checksums against the AccurateRip database

I think this gives much more confidence that the result is correct. The tags seem a lot more detailed with whipper too.

What I appreciated most about 'abcde' was that just prior to the rip it would open up the CDDB output in 'vim' and allow quick and easy edits to what are, sometimes, horrific titling and track entries ...

It's a very nice workflow and avoids a lot of cleanup ...

I second this question. I've used both before; the user experience is basically the same, and there's no audible difference between the two.