I have the sig bdx binos. I bought them for the rangefinder. I noticed right away they werent as clear as the zeiss conquests they replaced. They are certainly acceptable though. And, for their pricepoint i feel they are decently priced for what you get.
Supposedly the Zulu 9 are the same as Maven B series above the B1 but in different casings. I have the the zulu 11x45 and can't see a difference between them and Mavens. Really nice binoculars. I can't speak to the Zulu's below the 9.