This product is 5 STARS. We needed to move from a hosted product to an in-house solution alomost two years ago and afterlooking at many solutions we decided to take the CANIT plunge. The experience has been terrific and we use this for both managed service clients as well as for a hosted Exchange environment.
The flexibility and scalability are both great and this runs in a virtual environement with no issues.
The Vendor also makes referrals based upon your location which has also been a plus for us.
Been using CAN-IT for over two years now for hosting various clients. The team at Roaring Penguin has done great job with this software. Highly configurable and often if it doesn't do exactly what you need out of the box the team at Roaring Penguin can make it do it. We needed a custom solution to login to a legacy mail service and they had no trouble writing the routine to allow each domain on the appliance validate credentials against this legacy box.
In terms of SPAM having used Barracuda for years, I have to say that CAN-IT has far better spam control. One of our clients is staffing agency so had lots of spam with words like work, resume coming in. Now clearly we can't block these words, after a little bit of tweaking in the first month we were able to eliminate around 99.99% of spam with less than one or two false positives per quarter. After two years most of our users don't even realize it exists, it's that good.
For most people getting 95% of spam removal out of the box willl be sufficient, but if you really want to get rid of the next 5% you can with this product.
We decided to bring our spam filtering inhouse and avoid expensive monthly fees by hosting it with a 3rd party. After months of evaluating products, we decided to go with CanIT. We've been using it for going on 2 years now and have never had a glitch, false positives are at a bare minimum, and support has been wonderful if we have needed assistance. I highly recommend the product and the company.