I have been looking at the Onkyo HT-S650 and the Kenwood HTB-505. Which is better? Kenwood has foward-firing 100 Watt powered subwoofer, but the Onkyo has a down-firing 150 Watt powered sub. Does forward sound better than downward firing? Please let me know which system is better, and if you know of a better home-theater-in-a-box under around 600 dollars, let me know. Thank you.