I've tried this firewall on my business computer - the one that never has as many problems as command central here! It's working great so far, no real annoying pop-ups and it blocks pop ups (for real!) as well.
Felt compelled to replace Sygate because I read it was purchased by Symantec and nothing Symantec (with the exception of GoBack) is EVER going on my machine. I'm not sure how it will change or if anyone has any info about it, but I'm getting out before Symantec slithers some of its nasty software on my machine. Way too many bad experiences with each version of Norton's to count and their tech support sucks big time!
Just wanted to put in my two cents about Kerio, it's worth trying and buying IMO.