I had to have two units of blood when I was in the hospital this summer. I felt SO much better the next day- like a whole new person. It was a little scary at the time, because they took it so super seriously. Two nurses checked and double checked each other, they had me check and spell my name- I'd been in for over a week at that point, and they'd been pumping stuff into me left and right, but nothing else was done this carefully. Even my surgery seemed more casual than the transfusion. It didn't feel any different than any of my other IVs, though.
My mom came down from Boston to be with me, and she offered to donate the blood for my transfusion, but it would have taken time to type her and do all the testing, and they didn't want to wait that long, so they used the blood bank. If that's something you're concerned about, you could talk to your doctor about using a family donation instead of a stranger's.