Not sure if I can validate the use of either for you.

Maybe the main reason for the use of the blind rivets may be the strength of the design? I noticed when removing the few expanding rivets that were on the car that they were easier to just pull out - no drilling.

My 04 had blind rivets installed and I replaced them with blind rivets per instructions. I guess you could always install the expanding types and, if the arches come loose, just replace them with blind rivets.

Me, I wouldn't mess around and chance having to do it over again.

Good luck and show us some pics later!

- Jose