Been using Mastodon and I can say it is indeed a very good alternative. One reminder to newcomers: choose wisely which server you'll join, depending on your interests. It will influence what and who you'll see first. Personally, I joined mastodon.gamedev.place which, as the name says, is turned for the game development community, however, it won't stop you from following people from mastodon.social, for example.

Be wary of Mastodon. While they were a good idea in the begining, their embrace/extend of GNU Social's protocol, as well as the walling-off of a large chunk of the federated network, is blatant censorship.