Me too! I haven't gotten one wrong yet. You just have to be really patient.
Indeed I always have those dubious thoughts in the back of my head is it right but, I try to find a piece I'm certain on then confirm it with more pieces so like I got a Roman, Wizard and King from Series 4they've all got cloaks and and the Wizard and Roman cloak feel similar but, you can feel the Romans headress, sword and curly hair piece, and the Wizard you can feel the staff and the beard and stuff, I can remember feeling for Elvis and I kept finding Aliens instead I knew that because they were the only 2 with cloaks but, kept feeling the square helmet finally I found Elvis's hair yay!
I've had 100% accuracy as well just gotta take your time and try to feel for the distinctive pieces if you're not sure just keep feeling or try another bag and come back to it