Setup a high volume mail server to work with Sendy

Hi, We have Sendy ([login to view URL]) working with AmazonSES right now, sending out our emails to our clients. We are looking to build our own mail server to work with Sendy to replace AmazonSES and to reduce our costs. We want to send out at least 20.000 emails/hour and NO we are no SPAMMING people! We send emails only to our subscribers. In your bid please include these: What's the server requirements you think you need, what CPU,RAM,HDD, how many IP addresses? etc. What Linux you are going to use, what mail server, why do you think that's a good combination? Have you done this before? for who? Can you provide reference? And please be short and right to the point. Thanks.