We've been using the product for a few months now after have looked at most of the alternatives. The biggest differentiators for me have been:
1. Really straightforward, scriptable installation 2. Intuitive view of the log data 3. Very quick and easy to select a time frame 4. UI is oriented to cope with lots of server creation/destruction (very useful for auto-scaling environments and not well handled in some of the other products)
We are very happy with the product - great job guys!