Yeah, I like my 78 A/DA Flanger. It's sort of a warm bubbly underwater sound, as opposed to the winding jet flanger sound.
I've A/B'd it with about 6 other flangers at the same time, and it's interesting that none of the others can fully capture it's sound. All flangers have a distinct sound. One thing you can do with an ADA is open it up and mess with the mini pots. They control some of the features on top, so you can fine tune them to your liking, even though A/DA probably doesn't recommend it.
We're lucky they've reissued them, so buy one while they're still available. For years, you were outta luck if you couldn't find an older one. I wish I had a new Final Phase.....and one of their expression pedals.