never let you know when you are due a renewal so the first you know is that your site is down and you can't get email
if you have a dispute with them they will make up all sorts of things to charge you for before they will release your domain so you are essentially held to ransom
website is really badly laid out - hard to navigate with odd popups all the time
expensive. domains were around £3 when I first signed up, now they are a tenner. Hosting was £15 for starter now its £19 and for no better service
if you have to make dns changes to your website like adding mx records it takes 2 days for it to happen.