what have you been using?

I have good luck with this Grafix product in 9" x 12" sheets. I prefer the matte finish, but gloss works decent too, it's just harder to see when applied: http://www.dickblick.com/products/grafix-all-purpose-frisket-film/?clickTracking=true&wmcp=pla&wmcid=items&wmckw=25205-1033&gclid=Cj0KEQjw04qvBRC6vfKG2Pi0_8gBEiQAAJq0vXPYOSuv_ofQIbvZbpmOE9Z6rY49tNCJNAm6PpPbQOwaAn4B8P8HAQ

Oddly, these guys make this frisket on a roll, but the adhesive is somehow different and often wants to stick to the substrate (most often a pinball cabinet) in areas when I go to pull it, where as the 9" x 12" sheets do not. It sucks to have to go back and remove adhesive from in between delicate airbrush work, so I no longer use the frisket on the rolls.

I also like to use yellow Frog Tape for delicate surfaces for doing areas of long straight lines so I don't waste frisket. The Frog Tape has really good edge block properties that stops bleeding.

I use that stuff, but in roll form

Does it leave behind pieces of adhesive when you pull it? Maybe I got a bad roll...

I've had that problem if you heat set your paint and you try to remove it before it cools. I've started to mask the area off then use the frisket on top of that so only the edge of the friskey is touching the board.