I started with Poser 1 - I read about it in a British computer magazine, and I remember calling Kai's Fractal Designs every month for a year before it came out, as they missed one release deadline after another before they would finally accept my phone order for "that 3D Manequin program" .
I still have a copy of every version 1 thru 7 installed on my G drive except Ver2 & ProPack (lost the disks in an emergency move due to a flood)