I use them for 3 domains with their Linux 'Home' package. As was mentioned, support is very slow. So far I haven't needed it. But they're reliable and have better than average speed. If you decide to use them I'd advise registering your domains elsewhere (they use a German registrar) and don't accept the 'free' software offer (it locks you into a one year package). Don't know if this would affect you, but the SQL databases (25 of them) are limited to 100 mb each.
I wouldnt use 1and1 for somehting serious.I remember,that when i was looking for a dedicated box they were the first i sent mail to.I got offer from various host for 2 weeks straight,and after i got my whole new box,they replied.Of course i didnt reply back since i would wait another full 3 weeks...
I had a free 1&1 account when they were doing a promo a while ago. It came with a shell account; I logged in with some esoteric username that I couldn't change (s19834785 or something like that), found out the system didn't have emacs, wouldn't let me run top, and was crippled in many other ways.
I sent them an email asking if they planned on installing emacs anytime soon. The reply wasn't very prompt (though in fairness within a couple days), and they said they had no plans to install emacs.
I have had 10 differrant GERMAN box's from 1and1 they were BOTH very slow some nights it wouldn't connect some nights it wouldnt work and some it would I called them up once and they just HANGED up took my money and ran I think..
Man 1 and 1 suck they told me I didn;t cancel my account the correct way. I said I went to you web site and then printed the paper and faxed it in I then called and they told me it was taken care of. I got a letter in the mail they wanted to send me to a colletion agent for 5 $ since i didn't cancel my account. I showed then the letter and that hoe on the phone keep telling me I had to pay the 5$ I said take me to court or kiss my you know. They said fine and thats the last i heard. They didn;t have my SSn so I wasn't to scared over it. 5.00 they people are crazy I have no problems paying 5 $ but the point was she was a B on the phone and I wasn;t going to do it then.