Steve:
I also use (because I have had the stuff a long time), Scotch brand 3M Fine Line Tape #218. It's not the blue tape, but is a light green and is a stretchy plastic. Comes in a variety of widths. Got it at the auto paint store. The 1/8" is very good on the contour and since it kind of stretches, you can get a very good seal. I have not had any problems with pull off. I can't comment on the cost difference, since I have enough of this to last me quite a while. Back in the '80's my brother and I were doing his car and we got more than we needed.
Jim