I use 1&1 on a regular basis,and have done so for a few years now and I would recommend them. Like most companies they have had problems, but these have never affected my usage, and by experience I would consider that they have resolved past issues.
Once you register with 1&1, you may find that they will contact you with special offers. Recently I was offered a free six month extension to a couple of my packages, which made a nice surprise. In general, their packages offer very good value for money with very little complications. Would add that registering a domain and receiving the Nominet document, now takes between five to eight weeks, depending on Nominets workload.But of course, your domain is registered to you on a 1&1 availabilty check, which is usually instant on contract payment.