Fastal, IPA is just Isopropal Alcohol....it works fairly well on dissolving certain adhesives and is safe to use on many surfaces...but you need a little elbow grease..I use it when removing the the adhesive from registration stickers .Acetone, and its sister solvent Methyl Ethyl Ketone or MEK is a really strong solvent and should take off dried adhesive easily, but if its spilled on the surface of your boat and not cleaned up, it can eat through the resin.......I'm surprised it was still difficult to remove the striping tape....maybe many years of sun aging added to the difficulty.
I checked the MSDS on that Goof Off stuff....the regular version has a blend of ethylene glycol Nbutyl ether, benzyl alcohol, tall oil and a couple of trace elements....not familiar with that mix of materials but I guess it did a good job on the old residue.
The pro blend is mostly Xylene with some Ethyl Benzene and traces of other stuff...Nasty stuff to use but the xylene factor works well. You don't want to leave that sitting on your finish either.