many of use have learned this leason the hard way. Just do a search in the disease section and you will see all the heart ache. a proper quarentine is a must the birds can look healthy and still be sick or carriers, the quarentine is not perfect but it helps a lot. So far you have been lucky but I would not push it. There is a guy on BYC who has birds with a variety of illnesses and myself and a few members have had devistating results from our purchase and I did a partial quarentine but they shared air space and infected some of my others. I culled all but 2.
