He means don't ride it too hard, if you look at the manual for it or online at the Profile site, it'll show you how to hook it up appropiately. They also have a little disclaimer before that section advising you not to over do it.
i have a profile 800sx and i like it personally. it puts out good power for the money. i bought mine 2 months ago but i want to get a jbl 1200.1 and im selling mine for 140. if interested let me know at kottonmouth@caraudio.com