If you are content with the sound of your Bose/JBL combo, then I would advise you to stick with separates and buy a newer receiver and sub. HTIB is fine for smaller rooms and nicer decor, but it doesn't have the impact nor does it offer the upgradeability options of separates.
I like Yamaha and Denon for good-value receivers (lots of folks seem to like Onkyo as well). Athena, Paradigm, PSB all make good mid-range subs in the 10"-12" range. I think you'll be happier in the long run if you go separates.
I am thinking about upgrading my home theater system. Currently I have HDTV, DirecTV/TiVo, VCR, DVD, CD, 7 year old surround sound Receiver, 5 nice newer Bose/JBL speakers.
I want to get a new mid-level 5.1 or 6.1 receiver and add a mid-level subwoofer. BUT, I am looking at all those Home Theater In a Box units, some of which seem to have pretty good sound quality. It looks like for the total $4-500 I would spend on a new mid-level reciever and subwoofer I could get a decent HTIB. Should I opt for a HTIB and sell my DVD, CD and nice Bose/JBL speakers (3 front and 2 rear)? My living room size is 12'x14' (about 200 square feet). I do not want the latest/greatest/loudest system out there. But, I do want good quality sound and have the option of expanding my system in the future (who knows, might buy a bigger house with a larger living room or want to play music outside, or add another speaker...).
Any thoughts?

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