BAT VK500

HELLO,I HAVE THE OPPORTUNITY TO BUY A BAT VK500 AMP FROM A LOCAL FRIEND. I HAVE HEARD HIS SYSTEM AND DECIDED TO GIVE IT A LISTEN OVER MY HOUSE.I AM GOING TO HOOK IT UP ON THANKSGIVING BUT HAVE A FEW QUESTIONS.THE OWNERS MANUAL DOES NOT LIST ANY SPECS.WHICH I THOUGHT WAS KIND OF ODD. HE SAYS IT IS 250/WATTS/CH. IS THIS CLASS A OR A/B???ALSO WHAT IS THE INPUT IMPEDANCE.I AM A LITTLE LEARY BUYING A PRODUCT FROM SUCH A NEW COMPANY.I AM CURRENTLY USING A FORTE4 AMP.ALL OPINIONS AND COMMENTS APPRECIATED. THANKYOU