**** some of you guys can be dicks. Most of you shouldnt even be posting in here because you havent used either amp or even a single product from either company.
Also there is more than one way batteries are rated. Just cause you dont use them all and obviously dont look into non standard batteries doesnt mean his arent good. Hell a 200AH battery is pretty good and has quite a bit of reserve power.
Finally on to the posters original question. The IA amps arent overrated, they will do about 1800 watts @ 1ohm and that is it period(if that). They will do more below that ohm load and seem to be very stable amps while doing it. I have yet to see one fry. Also I have not used this particular MA amp but others I have used are very well built and are very stable as well. The IA can take 16+volt setups and lower ohm loads right outta the box. The MA may need to be moddified for this to happen.
If you need 5000 watts and have a 12 volt system and are trying to run JBL subs why not just get a JBL/Crown 6000 watt amp.