Don, I think it's cute that people think PAM is "safe" or specially formulated for safe use around reptiles, but that other permethrin products are not.
I read Jamie's piece advocating the use of of PAM and it's explanation of why PAM is somehow so special that other permethrin products of the same concentration cannot be used in the same fashion. I gave a printout of that post to my friend Vic's wife who is a chemist for the Ortho Division of Chevron.
I won't go into her explanation of how there is essentially little to no difference (depending on the brand) between treatments and how legally Pro-Products by virtue of their instructions and the semantics involved in the EPA and USDA approval processes can make the claims no one else can.
The semantics of that approval, however, are paper thin reasoning for me to pay the premium for PAM. When dealing with prophylactically treating new arrivals, I opt to use a more attainable (both in terms of purchasing and price) product and have had zero issues with it.
This argument has been covered on this forum and elsewhere. Anyone who wishes to investigate for themselves should find more than enough information to make a true informed choice.