I have never shot any of these three Mathews bow, but have an opportunity to buy a Z7 new in box. I was wondering what the difference is between the Z7 and Z7 Extreme in terms of draw cycle smoothness, are cams the same, how is the valley draw feel, and do either one have a dead end back stop like the Elite bows? How do these Z Series compare to the DXT? Any information is appreciated since I don't want to lose this opportunity to buy a new Z7. Is it easy to tune a Z7 and how accurate is it?