I’ve had an account with 1&1 for, oh, many years. Never for hosting but simply for domain handling – specifically artiss.co.uk.
However, needing to install SSL on this domain, my host (Tsohost) can only do it if the domain is hosted with them and 1&1, well, they won’t give me SSL because I don’t have the domain hosted with them. So, the easiest solution was to move the domain to Tsohost.
Sadly, 1&1 have made sure this process isn’t easy.