That's correct. If you get the black sapphire and want a metal band, you'll have to deal with the color mismatch or hope Garmin releases a black metal band.
I was in the same boat, but decided on the black sapphire with plans to eventually get a leather band.
That is terrible! I currently have the F3HR with a metal band - if i want to use the band i already have which cost me £159 then i have to buy the 5X which i think might be too big and has lower battery life (neither I want). I think the F5 looks sleeker and therefore better as an all day watch. But to pick the black watch but not have a black metal band to go with it seems retarded!
I might just have to wait and see if they release a titanium version....