I actually started on Kbin.social, but then it got shut down, Kbin died and now fedia.io seems to be the largest one running MBin. I like the interface on MBin and I guess it’s good to have a diverse fediverse with different services, but at the same time, why use mbin when everyone congregates on lemmy instances? The local magazines on fedia are for the most part, quite dead, when compared to lemmy collections. In the end I feel like there aren’t enough people to go around to support many more services like MBin and Piefed.
I personally don’t use mobile sites, but the only plus for Lemmy seems to be the thumbnail size. Aside from that they seem both kinda meh. There’s plenty of apps for Lemmy though. Mbin only has Interstellar right now, but the Eternity devs said they at least plan to add mbin support in the future, which is what I used on Reddit back then too (Infinity).