I have the 49mm diameter Minolta Rokkor 24 f2.8, it was one of the reasons I bought into Minolta's. I also have a Zuiko 24mm f2.8. Anyway, there are a couple of different versions of the Minolta lens, the 49mm I have and a 55mm too. Both AFAIK have a similar "floating element" whatever than means. There's a write up on Rokkor files...
http://www.rokkorfiles.com/24mm.html
That guy mentions the front rotating and the lens pictured is the 55mm version, my 49mm lens doesn't have a rotating front.
I read somewhere that some think this is the best 24mm design ever made but I don't know which version that claim is for and I don't believe it anyway as doubtless modern high quality "Art" type lenses will blow it away. It may hoverer be a classic design

and from what I remember Leica rebadged a version of it.
I'd say that my Rokkor is better than my Zuiko. I don't have a 24mm FD, I stopped at the 28mm f2.8 with FD's.
I've posted a few pictures taken with the Minolta in this thread but no doubt it'll be a PITA to find them. Or maybe not...
https://www.talkphotography.co.uk/threads/the-glorious-a7-but-its-all-good-thread.511885/page-279
I've taken quite a few pictures with this 24mm but of course as there's no exif it's down to memory and I can't always remember what I used... I only remember these pictures because I posted them here.
My review...
It's a good enough lens and better than the more compact Zuiko. It's sharp enough without too many optical nasties and whilst almost certainly not up to comparison with modern Sigma Art type and similar lenses it's perfectly usable for real word shooting and even closer viewing on screen.