In April 2016 our uptime was 100% as measured by Pingdom.com
We did have 21 separate system outages with had zero service impact. The network is architected to be self healing and redundant so a single failure or even a failure of one data center will not impact customers.
Couple our uptime with our commercial antivirus, 24×7 technical support and excellent spam filtering engine, we are approaching enterprise grade reliability and performance for our clients.