I have a sample IJ, an upcoming restoration. PFR has had the playfields for over 2 years now, I am sure they will be returned someday.
It's a very rough sample IJ, but with the restoration I have planned, any sample IJ is sufficient.
Here are some (but not all) of the items that make a sample a sample:
Small heads on the carriage bolts holding the PF slides in:
No buy-in button
Stainless side rails on POA
Different 'Super Jackpot' insert artwork
Lost Plastic
Illumination for the lost plastic from the factory
Extra lamp piggybacked off big lamp board, which is different from production
Extra holes drilled on mini playfield
Backbox speaker panel with lamp board from the factory
Complete gallery link for game pics here:
http://gallery.myhomegameroom.com/gallery/ij_sample_asrecd