If you start it up and forget about it, Fulcrum would be better since it can deliver better performance after it's synced.
If you plan to start it up every now and then when you need it and don't mind if a wallet with many transactions is not lightning fast to receive, Electrs is better choice.
The other question is if I really need it - I have electrs running and I really do not feel I must change it to something else. But you know - numbers in performance comparison are tempting.
Maybe one day if I have nothing better to do...
If it ain't broke don't fix it.....
Anyway, got fulcrum running and synced. No real issues there. Will say that outside of the BTC syncing issues that I mentioned earlier that it's a much simpler run then electrs.
A few lines in a config file, run an exe, wait, done.
And this I think is a good thing. People who want to do it themselves but don't have a good knowledge of OSs and other things can with very little work have their own private electrum server running on an old Windows box. Yes there are 100s of other things to consider and so on. But for a close to run and done pre-compiled solution it does work.
-Dave