re: the SX, the quality is there, "high end" features are not (its not meant to be high end, its meant to be an affordable spa)...and yes you are severely limited on your tub selection if you only have a 6' x 6' space...99% of the smallest high end tubs are going to be over 6' in either width or length...5'8" x 6' 4", 5'5" x 7'...etc etc