Re: What's so wrong about mounting amp on sub box?
I didn't have any problems when I did it. If you're running under 1,000w and have a solid 3/4" mdf box, it shouldn't be a problem. Many will recommend using rubber washers under the mounting feet to dampen the vibrations. Or if you have a huge enclosure with no bracing, you're probably going to get a lot of flex in the box, which would make it a bad idea.
2009 Hyundai Elantra - Budget Sound in Progress
HU- Kenwood eXcelon KDC-X994
Fronts- Crescendo MP6 mids, Vifa Ring Radiator tweets on Arc KS300.4
Subs- Single SA-10 on Mmats 2000.1 @ 1ohm
Misc- 1/0 CCA from AT, Big 3 in Stinger HPM, and AT 60 mil deadener
Bought from: Inferno333, select127, treesive, Kangaroux, DonH
Sold to: coolest user, Psychodrama, MidgetClown, mr.tigger, av83