it can be run at .5 ohms...i have run my sx1250.1 like that for around 2 weeks and nothing happend.. but if u dont no what ur doing i wouldnt do it....
when i used to have the kicker kx1200.1, i ran it at .5 ohm for like 2 months without any problem. i sold that amp to my friend and he has been using for a year now without a problem. of course he is running it at 1 ohm but still after the abuse i gave that amp, its still running well.