Well-written review. And I do agree that while the rapping is solid, the beats are good...
But I don't find this to be even remotely funny. I didn't think the "Chronic Cupcake" or whatever song was funny when it was released, either. It's 2009 and the "nerdy white guy rapping to be ironic LOLZ" thing is pretty played out. Why not just admit they want to rap and try to write something of value? They have the skills, so why not? Or at least try and write comedic hip-hop songs that are a bit edgier instead of relying on the "it's funny because we're not supposed to be rapping" factor? See also: the Bloodhound Gang and the army of nerdcore rappers out there.
There's a fine line between clever and stupid.
That being said? Sandberg's a pretty funny dude. And Hot Rod ruled. He should stick to traditional comedy.