IMHO their support leaves a lot to be desired but if you have time or are experienced they are a good economic host.
A little off topic but related sort of. The thing that gives me the hardest time is making the DNS glue records because the interface is so poor. I mention it here just in case any one else is stuck on them.
Simply:
A glue record is an A record in your own domain file that points to a DNS server inside that domain.
On 1&1 (after moving the domain to them) you need to create a subdomain (i.e. dns.your-domain.com) then wait for it to get fully created. Once created you go the the EDIT dns settings menu and click "other IP" then set the dns servers IP there.
Now you can go back to your root domain (your-domain.com) and point the DNS record from 1&1 or your old host to your dns.your-domain.com address. Your domain will be back up as soon as the information propagates with all your old records and manageable by you directly now.