I know all about bringing in Finches into a grey home. Finches hide illness even better than the big guys, so a quarentine is a must. I have found that if they don't look, act, or have any other signs of illness within the 45 days they are fine. The only thing I would worry about the finches carrying in with them is Polyoma (I'm sure thats spelled wrong). All small birds can carry it, like cockatiels, budgies, lovebirds, and finches, but most pet stores and many breeders vaccinate baby parrots against it. If you don't know if your Bently has had these vacs yet call up who you got him from and ask. If not you may want to bring him into the vet for it. It's 2 shots given over 2 weeks.