IME BF can darken silver *way* too much for my taste, but that's just me.
I *love* how 4-Star UPP looks on silver (use it on my S8) but the durability is so-so and the protection is virtually *NIL*.
My fave on silver is FK1000P hands-down. Perfect LSP for that color and as durable and protecive as conventional LSPs get IME.