1&1 is a very big company that deals with web hosting and domain registration. I have used them to register about two domains in the past 2 months and so far so good. No bad experience with them and they are pretty cheap. Cheaper than most other registrars out there. But they also have some downsides compared to others.
1&1 gives out most domain extensions for as low as $5.99. That is a much cheaper price even compared to NameCheap, my favorite registrar. They also give out a free whoisguard which is excellent because so far, NameCheap is the only other registrar that does that for free for purchasing one domain. GoDaddy gives you a free whoisguard if you register 5 domains or more.
1&1 domain transfer fees is something I don’t like. Transferring your domain to another 1&1 account costs at least $5.99 per domain and more for other newer extensions. I think that it’s not right to charge for transfers. But otherwise, 1&1 is a very reputable and good company. If you want to save, try them out and see what happens.