I'm currently working on upgrading a pair of B&W 602's for a friend. Doesn't take much to improve them. They're ridiculously overpriced for how they're made. The cabinets are real cheap fiber board, and not even MDF! And the cabinet ring like a bell. No bracing whatsoever in them! I was quite surprised. And the x-over is one of the cheapest I've ever seen. Dental floss sized inductors and bottom level parts all round. Even the binding posts were full of magnetic metal.
100£ on upgraded parts, and it will be 10 levels better. Also gonna add a notch filter to bring down the higher frequencies a couple of dB, as they are quite "shouty" at the top end, as all B&B's are.
I just can't understand how and why they get away with using such crap parts in an otherwise OK speaker. Changing the parts and stiffening the cabinet will take it from OK to Great!