I agree. When I purchased the vx3 I was debating between a mark4 and couldn't find any significant differences between the 2 scopes. The mark 4 has a "beefer" tube and the m1 knobs. The glass is the same. I like the target turrets over the m1 because they are covered. Not worth spending the extra money for the same glass IMHO.
My honest opinion is that the VX-3's are fantastic for the money, but the Nightforce are phenomenal for the money it's a lot of money when you think about it but hey if you are willing to spend near that amount on a Vortex or Leupold then get the NF they are proven and they have the lifetime warranty. Plus one thing that has me concerned with the Vortex is that I haven't been around any, but if the warranty is as good as the one on my Viper HD binos then they might be well worth it at this point I can't say though with no real experience or use of them. The VX-3 CDs is awesome too one of my buddies just got one and he can throw it in his pack without the bulky turrets catching on anything.