In the 70's I was into them a lot. "Fingers" was definitely my favorite of Airto's. Another CTI album "Free" has some decent stuff on it, too.
I still have 2 Opa albums but never listen to them. I guess that says something.
I still like the early Flora albums. "Butterfly Dreams" definitely holds up for me. Maybe it's the Joe Henderson presence. All of the Milestone albums have some interesting things, actually. She got sidetracked when she signed with Warners and became even more commercial, although "Nothing Will Be As It Was Tomorrow" is worth checking out.
What really got me into them were the first 2 "Return to Forever" albums, though - S/T and "Light as a Feather". Those still hold their interest and sound contemporary today - 30 years later.