For the price the Wharfedale is the best pick in that lot. Depends on what speakers you already have or plan to get. The Diamond 9 family from Wharfedale will match their subwoofer very well although you should also look at SW-250.
Naive, as a fellow owner of a Yamaha HTIB setup I feel your pain. The subwoofer is a disappointment. You should be quite happy with the Wharfedale SW-150 subwoofer. It gels very well with Wharfedale's own Diamond family as it is designed to do so. So you should audition it to see if you like the pairing with your own speakers. The build and output quality are well renowned so no problems there.