I've been a Horizons 3.8 player for 2 years now. When Odyssey dropped, I ignored it. Still haven't bought it. But now that we are forced to upgrade to remain with the live game, I bit the bullet and thought the game would crash and burn with sub 30 FPS on my modest laptop with an Nvidia 1060.
Well.. everything on Ultra and I am able to get stable framerates between 30-60 FPS.. including planets, stations and settlements. I'd say sometimes it runs even faster than Horizons 3.8. Update 13 was pretty good but I think Update 14 really improved things a lot futher.
For me personally, now there are zero reasons to remain with legacy. If you are like me afraid that Horizons 4.0 is going to tank your performance, don't be, give it a try.
My ONLY complaint is that landing on atmospheric planets is not made as a paid DLC… I'd gladly pay 20-30% of the price of full Odyssey (which is of no interest to me) to be able to land on those. Right now , there is an invisible wall in-game preventing us to land… so it should be pretty easy to remove as a paid DLC.
Source: https://www.reddit.com/r/EliteDangerous/comments/z98s4h/horizons_40_is_awesome_finally/