I had this in the past, and actually today. The client was moving to a local server and he emailed me asking me if I wanted a testimonial, feedback or anything relivent. This really put a smile on my face. I think offering the host something like testomonial, feedback, ratings or anything relivent would be just fine.
Everyone moves hosts at some point the hosting company shouldn't get upset unless there really small and that money makes there bills each month.
The problem, though, is that sometimes, you really find out just how good your original host was (has happened to a few of my clients) after you've been with the new host for a few months. I had a customer of a customer that actually came to me, simply because he couldn't get half the stuff he needed... and yes, this was a guy that went with HostGator...
Douglas Hazard - Certifiable Sports Junkie and Sports Community Enthusiast
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