Which of these?
http://www.klipsch.com/products/lists/subwoofer.aspx

What I currently have
http://www.yamaha.com/yec/products/productdetail.html?CNTID=200489

Both these subs look pretty comparable on paper except for the amp sections and the response range due to the smaller woofer in the 10d. Based on what I see here looks like the RW-10D has more power and better features.

However the reason I am upgrading is to get more power and deeper reach in the frequency area. I currently have a Yamaha SW-315 which has a 10" with 250w. I don't want another sub that almost shakes my beer off the coffee table. I want to catch it just before it does:D

What is your budget and why/how have you narrowed you choices to only these 2 subs?

I can't believe they still sell the KSW. I guess someone must like it. It is downfiring, if that matters.

Between those 2, the RW-10d is the better sub.