Are these BTAs healthy?

[Mozby's Reef]

I was looking at BTAs in my LFS and all of them seem to have a bleached center. I can't find much information on it, but I recall reading once that a white mouth is a sign of poor health? Can someone confirm this for me? All their BTAs have a whitish center and therefore I'm hesitant to pull the trigger. 

 

[pgrVII]

Look fine to me . With the mouth its about it being tightly closed (unless pooping of course) youre seeing a normal color trait on a bta.