which woofer do you prefer

I am in the market for a subwoofer (again) and have narrowed my choices down to the "A-list". I have used several subs over the years, some that lived up to their billing and others that fell short and I am alway curious to see what other audiophiles have found to be their woofer of choice. I have noticed recently that REL subwoofers are consistantly coming up in the used market. I was always under the impression that REL is essentially state-of-the-art and found it curious that so many of them are traded second-hand. so what woofers do you like? DIY, REL, Velodyne........I know there is a tremendous amount of smaller companies that make high-quality, high-end woofers and if you won one of those woofers, I would like to hear about it. Thanks