Haven't tried these yet, but thinking of buying one to try. http://www.wraptools.com/Wrap-Vinyl-Backslitter_p_80.html
Those work great but I'd definately recommend the one with the blade holder in teflon since the one with the brown strip wears out quite quickly, gets sticky and not working well. The one with black teflon works superb and although it's not cheap it's worth it's money:
http://yellotools.us/Labeling/Special-Tools/BodyGuard-Knife-Teflon.html
Everyone has their favorite gadget but know that any device that relies on blade depth is inherently flawed. This sort of cutter, at some time or another, will not completely cut the backing or will cut both the backing and the vinyl.
A device that has some sort of platen the slides between the backing and the vinyl can be a reliable solution.
Those work great but I'd definately recommend the one with the blade holder in teflon since the one with the brown strip wears out quite quickly, gets sticky and not working well. The one with black teflon works superb and although it's not cheap it's worth it's money:
http://yellotools.us/Labeling/Special-Tools/BodyGuard-Knife-Teflon.html
Get it from Amazon, it's called a gift wrap cutter and its way cheaper
https://www.amazon.com/gp/aw/d/B002...per+cutter&dpPl=1&dpID=41YhhqESxnL&ref=plSrch
Yikes... that's expensive. Not saying it doesn't work, just expensive