Hi all, I'm about to change my current B&w 603 s3 speakers. I'm thinking of B&W Nautilus 805. I'll mainly use the speakers for listening to music and less for movies. Are 805's good choice to replace the 603's and what else do you recommend for budget of 1500 pounds? Will I need to add a sub to them? What about 705's? They are about half price. Thanks, Ben.