Yes, that's junk.
The 90 watt claim is ALL over the place. Is it 90 watts RMS? Why is it such a high signal to noise ratio? Most amps rate down to less than .1% at power handing capacity.
The amp linked delivers power to all channels driven at all times. So, it's not a 'max' power rating, but a pure power driven at all times. It should also be considered that you would need 3 amps, then to split the sources three ways to get that power out the door, which means dealing with a great deal of extra cabling and running power multiple ways.
In the end, the multi-channel amp I linked to has a original MSRP of about $2,400 and is only the deal it is because it came out of a system used, but eBay used demands that it is fully functional, and you get your full money back if it is not. It is a very serious product and can really deliver.
I don't 'hate' Pyle, but they need to be considered for the quality that they are known for. Typically it's cheap, but works okay. It can be very unreliable, and it often fails to meet specifications, or uses advertising to confuse the specifications that other manufacturers lay out directly.
It is always worth it to read a specification sheet that lays everything out...
http://www.sonance.com/product-archive/91779