Not a whole lot. One I used had no down votes and another kept going down. So I just stuck with lemm.ee but alot of the communities I use are on other instances. That is what I didn't get at first, that you could subscribe to any community on different instances unless they got defederated from your instance.
I made three different accounts but I really didn't know what instance to use at first. Now I have landed at the only one I use.
What are the differences between instances, functionality wise?
Not a whole lot. One I used had no down votes and another kept going down. So I just stuck with lemm.ee but alot of the communities I use are on other instances. That is what I didn't get at first, that you could subscribe to any community on different instances unless they got defederated from your instance.