Kicks isn't 100% safe un-atteneded for one simple reason. BLIZZARD BUGS!!!!
Seriously, you will reach quests that have a buggy spawned mob, or a bugged quest chest (Mt Hyjal Springs to mind for both) or similar. Doesn't mean it's kicks fault! But when your toon spends 2 hours engaged in combat with an evading mob, or looting a bugged chest, walking back 10 feet and then waling back up to the same chest and trying to loot it for 2 hours, anyone looking on will know your a bot.
I love kicks profiles, I've gone from 1-90 many times with them, I simply would NOT do it unattended if you wish to keep the AC.
A more current answer for you though: I have been using Kicks up to about a week ago (been a hell of a week at work so have n't had time to play wow) and no bans. Like always, Bot at your own risk.