The fact that this package has everything you could possibly need, with very little going wrong.
I'd be lying if i said there wasn't something we disliked about it but so far no problems have come up! Easy setup (we set things like number/size parameters before even installing). It's not cheap compared to other packages out their but once installed its hard getting rid off them as they are great value at around 200-300 per year which can really add up especially when every server in our office needs one these tools!! Monitoring servers 24x7 - alerts were sent right away whenever an attack was detected or any suspicious activity occurred (such attacks included viruses such as malware etc.).