So you flinched and made a bad shot with a 30'06, then went and bought a 7mmMag. Yeah, that makes sense. I made a reference to mag calibers, deficiencies and penis size in the .300 Mag thread, seems to apply here.
Why compare a 7mmMag to a 7X57? Sounds like you'd have been better served to step back to that wimpy 7mm08 that I like to shoot. It'll kill deer farther than most people can effectively shoot. I stoned a doe with it last year at 322yds. I own 4 7mmMags, I just rarely hunt with them for deer, the last one I shot was just about ruined from the bullet.
Or even better get a .243 and practice with it and get rid of that flinch. When it is time to hunt deer, you are good to go.