Is it ok to match speakers with different brands? I know matching the front and center is important, that's why I purchased the B&W 602S3 and the LCR60. But does it have to match with the subwoofer and the rears? Is it really important? Right now I have the PSB Subsonic 5 and the Alpha B. It sounds good, would it sound way better if it was an all B&W system? I also have to take into consideration the cost. I'm a beginner, hope you don't mind