For $500 both are junk. IMO HTIB territory should be cheaper than you can peice something better together. For $500 you can peice something better together or at least get a good start on something better. However you can get the Onkyo s3400 over at amazon for $250 right now. It does have a passive sub. Which makes it kinda non-upgradable to an extent. But for that price if you just want a cheap HTIB and are ok with starting over later when/if you upgrade to something better, it will probably do the job.
I personally wouldn't bother with a system comprised of only sony bookshelf's. Nor the $500 denon system with plastic boston acoustic speakers. Heck you can get the boston acoustic classic 5.1 system in black for $199.99 right now. Add a receiver and it'd be better than the denon system above as at least the speakers aren't plastic.
Furthermore for $500.00 or a tad over you'd be better off with a 5.0 fluance system, add a 5.1 receiver, and add a cheap dayton sub.