Originally Posted by Petden
Purchase individual speakers. Good subs go a long way in the enjoyment of HT. When it comes to subwoofers you want to purchase from a company that specializes in them. Another important considerayion is the number of subs you are willing to purchase. Multiple subs offer better sound quality because it can smooth out the room response. A single sub may give you the output you are looking for however it doesnt offer the best frequency response.
If you are willing to purchase your ht in steps you will get the most out of your system.
If you wanted to purchase dual subs right away i would look at the rythmik lv12r. http://www.rythmikaudio.com/LV12R.html
If you dont mid purchasing one sub at a time the PSA XV15 and XS15 are great. Another really good sub is the svs pb12.
Consult the AVS subwoofer forum
and you'll find people that will repeatedly tell you that the major Internet direct subwoofer vendors--SVS Audio, Rythmik Audio, Power Sound Audio, HSU Research, and Outlaw Audio--offer far better values than traditional speaker company subs, often even better values than subs from those speaker companies costing twice the price MSRP.
If well placed, dual subs offer the benefit of providing a more even frequency response through a wider seating area. Might want to research dual (and single) subwoofer placement as your contractor may not be wiring well for that. Just because your contractor has been involved with expensive HT setups does not mean he's knowledgeable about sub placement (although he might tell you he is--LOL).
As for in walls vs. conventional speakers, I agree with everyone else. You'll do better with regular speakers. Plus, if you get the upgrade bug later, you'll have more options to choose from
If you have more questions about subwoofers, best strategy would be to start a thread just for your sub purchase in the AVS subwoofer forum.