If you aren't obsessed with this game there's no reason to play these over the steam demo currently available. The steam demo has more features and polish than either of these. I played the demo levels a dozen times and came here looking for more to play.
You can't throw the melee weapons in V1 of the demo. That's all I found different. There's probably more differences but I cheezed the level by jumping over a wall in V1 so I skipped like half the demo.
Go play the steam demo, it's a much better sell than these even though I enjoyed all 3 demos.