I'm going to have to say negative on that one. In order to use this, you need to light it on fire, and drip the flaming drop of melted p-tex(resin) onto the hole/scratch/dent/dimple.
Fire + Finished guitars = bad IMHO
You hold it far enough away that the flame isn't touching the guitar. Not that hard to figure out really.
Plus with a poly finish not like a candles going to damage it unless your super careless. The flames when i've done it are really tiny.
I've fixed a few cheapies this way when I needed something quick and easy that would look okay.
Part of the reason I did this is many factory finishes are PTex resins. (per a friend who does a fair amount of work for Fender/Jackson/Charvel)
I know he's already chosen a finishing option, but I really want to put my foot down on this.
Step 1: Light P-Tex candle
Step 2: hold p-tex over metal tray to catch unused flaming p-tex drip
Step 3: Drip flaming p-tex into desired cavity
Now, when you're dripping into the cavity its important not to hold it up too high. What'll happen if you hold it up too high is it'll splash, and leave unwanted "dots" which will melt into your finish. Chances are that while you're holding it up too high, you will not get the p-tex into the cavity, but more around the cavity than anything. In the end, you'll be doing a lot of extra work with your guitar because there will be a bunch of burnt dots all around where you're refinishing. Please DON'T use p-tex on your guitar. There are SEVERAL other ways to refinish/buff/fill/smooth out a few dents.