I've owned many of these types of products and tested them all for well over a decade. Some leave
all kinds of visible residue, flakes, and/or chunks on the cards. Grip stick applies pretty cleanly
and invisibly.
The video download that comes with Grip Stick is much more thorough than
others. Lots of value here compared to buying pre-prepared decks.
I've always liked a stick
style product over spraying because there's no dry time, no need for ventilation, etc.
It
will take a knack to know how much pressure to use when applying. You don't want to be too light,
but you also don't want to be too heavy-handed. Like all good magic, it will require a little
practice.
I'd suggest making a "sacrificial" deck and treating each of the 4 suits with
different amounts of pressure. Each packet provides enough cards to test the results. Then you'll
know where your personal sweet spot is.
Anyone who says this just "doesn't work" for them
simply hasn't done enough trial and error - and you certainly don't need a lot of experimentation to
hone in the results.
So far for typical decks like an ID, I find the Regular strength to be
ideal. The Extra Hold really is quite strong. I'm sure I'll find an application for it, but it's
definitely harder to separate the cards with the Extra Hold, as advertised.
One stick will
be enough to prep dozens, possibly hundreds, of decks.
Best version on the market!