SpamTitan does it all. Ease of use is a big deal for us. We're a 2 man IT department. Having something that's easy to move around in and not time-consuming is a must.
SpamTitan is a pretty solid product. There's not really anything to dislike. If I did have to pick something, I would say the length of time in between software updates. It would seem to me that we would see more "updates" than what we do see. The flip side of that is, if the product is solid, updates frequently aren't necessary.
I recommend giving SpamTitan a try. I think you'll find it's very user-friendly. In the past, we dealt with a huge amount of spam. Thousands daily. We have cut down on the amount of unwanted mail drastically.