This month, one of my domains was up for renewal. Currently I own four domains and they've all been with 123-Reg for many years. However, the service I've had from them and the communication in response to a query was pretty poor - I realised that I'd had to contact them the year before regarding a renewal as well! So all in all, I decided to take my business elsewhere.
I've moved all the domains to Mythic Beasts, a UK based company that I'm hoping will provide a better service! I'm also considering moving my email and hosting there for a one stop shop, considering that Fastmail have now removed file hosting (though, I still have it as a grandfathered account) though in fairness, staying with Fastmail might be a good option, as it offers some better features that I might get with another host, such as an app and contact sync.