The SPL mark 2 series were reviewed by John E Johnson in Secrets of Home Theater & Hifi here where they were summarized as being some of the best compact subwoofers out there for their price.
Unfortunately the quote "for the price" has a sting in it's tail as whilst an SPL-1000 sells for a very competitive $829 (£430 UK equivalent) in USA the price has more than doubled by the time they are sold in UK which has very much restricted it's appeal over here when priced against subs like B&W ASW675