If I had to pick just one, I'd say v1 Falcon. I love the design, his outfit, cool shotgun, beret, colors, and a swell backpack. The cartoon and comic may have not done him justice, but as a toy, he was perfect. He had a good military balance when GI Joe was starting to get weird. I used him a lot.

But until 1986 or whenever he came out, my fave was probably Flash or Tripwire. Those guys took the backburner when cooler figures showed up. And Tunnel Rat, Muskrat and Repeater quickly became part of my top5 and always used.