I did in Costco many times, no problems, however I did check the pictures and 2 times I immediately asked them to re-do (one time the face was too big, another time too small, I think it should take 50% of total space on the picture), when I took pict at Costco I had the immigration sample with me showing the dimensions, and they re-did for free when I asked them. No problems with INS, worked for I-485, EAD, AP, visa revalidation. Last 2 times I did myself, printed out on photo paper, it also worked (for EAD).