its hard to come buy for good customer service, but i feel that you prolly ever wont be able to pinpoint the exact cause of the bleaching unless they came bleached or unless your tank got too hot or cold or it could be a number of reasons, and thatswhy there is a risk...umm, not to be rude or whatever but why wouldnt you want them overnight shipped, i mean you dont want corals out in shipping for a few days do you, maybe thats why they got bleached, you never know what it could be, if it were me i would take it on the chin and pay the overnight shipping, because i know there is a huge risk factor...at least hes willing to replace them for you so thats pretty cool...the pets stores dont do that on salt water stuff around here...they dont replace nothin even if it is there fault the corals were bleached....look on the bright side you can always tell people you have rare white monti caps...hahaha