I am on a tight budget and tight space requirements. I don't want to spend more than $200. I know that I can't get a good sub for this amount, but its all I can spend. I also have a space requirement imposed by the wife. It really can't be more than 10 inches in width. That just how the room is and how I have my Ht set up. So I have come down to these 2 choices:

Yamaha YST-FSW100 it has a 6.5" width which is very nice.
http://www.yamaha.com/yec/products/productdetail.html?CNTID=200143&CTID=5003300&ATRID=1000&DETYP=ATTRIBUTE

I can find it for around $110-$125 on ebay.

Another choice is the Acoustic Audio 8" sub. Its about 9.5" in width.
http://stores.channeladvisor.com/thedeepdiscount/Items/acoustic%20audio%20rwsub8%20ha%20v1?&caSKU=acoustic%20audio%20rwsub8%20ha%20v1&caTitle=Acoustic%20Audio%20RW-Sub%208%20Inch%20Powered%20Subwoofer%20300%20Watt%20Home%20T heater%20Series%20Sub%20Theatre%20Bass%20USA

My question, and I know this is very subjective, is which one looks like it would be better. The Yamaha has a 6.5" driver, while the Acoustic Audio has a 8" driver. Just based on that I would assume the 8" would be better but maybe I am missing some other important info. I am leaning towards the Yamaha because of the size, but I want to make sure that I am not getting shafted on quality and if I just compromised on 3 inches of width I could get much better sound. Thanks!

It's hard to tell which one sounds better just by looking, but a 6.5 inch driver simply cannot move much air. Based on that, I'd bet on the Acoustic Audio sub doing a better job.

Thanks. I know its hard just based on specs, and even room size and shape come in to play. Maybe someone has experience with either of these subs?

I have an 8" in my downstairs area and it really doesn't cut it.

I was able to get my upstairs 12" sub to fit under an end table and it's barely noticable. If you can find a way to do that and meet the WAF, then WalMart has a full-function 12", w/120 watt amp for $125+sipping.http://www.walmart.com/catalog/product.do?product_id=9893812

I went with the yamaha since it fit my size requirements better. Thanks for your help.