Our company has been using a managed server at 1&1 for about 18 months now and have mixed feelings about them. We like the features they offer and the user friendly admin control panel, which along with the price make it a compelling choice. However, we also have 25 email accounts set there and have experienced annoying instability for the last year. Like the previous comments, emails have recently been delayed from hours to up to a day. Since email is a primary form of communication for us, it is quite disruptive. Considering that email is a commodity service now, I don't understand why they have so much trouble with it.
In addition, there are apparently many 1&1 customers who are known spammers, which can prevent our corporate emails from reaching external addresses (like our customers) because their email filters/blocks emails coming from 1&1 addresses (known to listed on many a blacklist).
So, if DNS propogation wasn't so lengthy and painful, I would switch us over to another vendor. However, the thought of switching to a vendor with potentially the same problems is holding me back from switching right now.
For now, I'm just wishing they get their act together.
Just wanted to share a horrible experince i've had with 1&1 hosting. I've been trying to cancel for several months and I'm still getting charged. The service quality is poor and the customer service is horrible. Just needed to vent.

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