I tried all of the apps out there including Sync and continued using RIF because, for me, it was simply a superior user experience to anything else in the market.
Aesthetics-wise, though, Sync and many others are much better. Sync is one of my favorites for sure. It's very pretty. I used it for a long while trying to make it my new alternative cuz the looks were so much better. It was very good. I can't remember why I went back to RIF. Must have been a trifling detail.
Overall I'm extremely happy to see Sync here. It's a high class app in what is a primitive environment I thought was not gonna be amazing due to the lack of apps and stuff. I'm 100% sure if Sync is finished here, there's no stopping Lemmy's growth.
In all honestly, I thought RiF was kinda meh compared to the other major 3rd party reddit apps. Still orders of magnitude better than the official app, but the general readability, UI, and smoothness of apps like Sync, Relay, Boost, and Infinite, were better than RiF. I personally used Relay because of the absurd amount of customization.