My favorite thing about SpamTitan is the level of control I have over inbound and outbound mail from an MSP perspective. The pricing also makes it very affordable. I was a GFI customer for a long time with multiple clients using their services. Since their pricing/sales model no longer fit my needs, I was elated to find SpamTitan and its ability to serve my customers privately from an MSP perspective. Also, I was able to get quick answers and I was able to buy the product directly from their website in minutes. Hands down, SpamTitan is the best product I have found in the past 5 years.