I'm not particularly impressed, to be honest.
Aside from the performance issues (which I'm sure will be sorted out), the UI is awful. Seriously, how the hell am I supposed to join a community on desktop? The "subscribe" button is just a bit of text!
I understand the idea of the fediverse is to be decentralised, but it just doesn't make for a great user-experience. The whole thing doesn't really "click" in the same way reddit does. On top of that, it doesn't really have a big enough userbase yet. On reddit, big subs like gaming and movies a packed full of users, yet their equivalents seem pretty dead here.
I'm never going to install the official reddit app so I'm sure I'll be fine with Lemmy on mobile when the performance issues are sorted out, but I'll probably stick to reddit on desktop.