I've only had positive experiences using Private Firewall, and near the beginning of 2014 (as a new member) I distinctly recall exterminator20's encouraging support when I'd chosen it from among a handful of free firewalls I'd read about here on MT. We needed a good firewall for our Windows XP SP 3 of which it's native firewall was sorely insufficient.
Private Firewall does it's job well, and this comes from a member whom likes adjusting settings (all are set to max) although I've not yet learned to truly optimize it's performance.
Apart from it's reliability, I do agree with my good friend, Rahadian, as it does in fact look like something out of kindergarten!! ...but if kindergarteners find themselves walking away scratching their heads, it would still be doing it's job quite well right out of the box. ..err, or download.
Yep its a good firewall program, I do like it once
I do highly recommended it to my friends which still using windows Xp OS, but again..every time I look on tray icon, kinda reminds me of this picture
Its not a big deal for me though