I use it because Solus = Budgie and Budgie = Solus in my eyes. Even tho Budgie seems to have some problems and shortcomings, it is stable and does its job so far and fits my taste.
Some things I've problems with are the "Start menu" very often it just is slow or does not open at all, depending on what is going on on my PC at that moment. Then it takes like 10+ seconds to open sometimes. Or when it opens I can not type in the search for example. (I've a 2 Monitor setup with nvidia 1080 card). That the multimonitor support is being worked on AFAIK. So, that would be a point that is missing, need taskbar etc. on 2nd monitor.
What I really miss compared to Gnome, is the fact that I could use windows key and on gnome it would give me that overview of all windows on my Desk etc. and the HOT corners is what I really miss, it was very convenient to use.
So the only thing that is annoying and needs some work imho, is the "Start menu" the other things are just what I miss, but I'm good when they never will be part of Budgie.
At the End of the day I still prefer Budgie over Gnome, because I think it is Solus. And it just works so far and never feels slow (except the start menu tho)