Never had any trouble with them, but also moving away from them is unnecessarily hard (the code sometimes takes a day to arrive) and they cover the entire interface with their paid hosting stuff which makes them a poor registrar. I ended up on them because of Google Domains selling off but got off them because very annoying to use.
I'd honestly be careful with squarespace. They are owned by private equity, advertise on countless YouTube channels, and at the same time their core market is under a looming threat from the AI companies.
You need your domain registrar to be stable and predictable. Their profile is not that.