Holy smokes. I am amazed. 2400 names at 1and1 and you've never had a problem with them?
Most of my domains are with 1and1, that's around 250 domains, and I have to tell you that I'm not going to register anything else with then. But its not because of their customer service or their prices.
The reasons are that everything takes too long with 1and1's interface. From the domain list updating itself when going from page to page, to the hours it takes for the DNS names to change or newly registered names to become available. It's all so slooooow with 1and1.
But the main reason I am frustrated with them is that you can't do some changes in bulk. To change the DNS names you have to go thru at least 3 different screens for... every... single... domain... name.
Like I said, I am amazed that you have 2400 names with them. How do you do it? How long does it take you to change things on so many domains? I honestly feel I am losing money because I am too lazy to deal with tweaking 250 domains one at a time on 1and1. I can't imagine having to do it for 2400!
Is there a bulk screen you are aware of that I am missing? Is there some way to automate things better on 1and1? I don't think so because I have asked them about it and they said bulk DNS changes are not possible.
Anyway, their prices are good and they make it real easy to buy new domains since your credit card is on file, so I will give them that.