So that you know where I am coming from, I'm a vortex fan boy without a doubt. I own 2 crossfires, 2 Diamondbacks, 6 vipers, 1 razor, 4 strikefires, 2 sparcs, their ranger 1000 rangefinder and a pair of diamondback binos. Man, I didn't even realize it was that bad until I went through all of them in my head, oops.
That said, I would pass on the crossfire line for any shooting beyond 100 yards. While the scope is certainly serviceable, it is light years away from even their Diamondbacks, let alone the vipers or above. The glass is comparable to other "budget" offerings from the big names, but I have found an incredibly small eye box on the crossfires and a bit of bluriness at high magnification. My 2 track well and are 100% reliable and repeatable.
But for not a whole lot more money, you can step up to the diamondback series and get more than your money's worth in my opinion. And while I do not know your purpose for the scope or your financial plan for the gun, I'd recommend holding out for a viper. Midway has the 6.5-20x44 on sale in the low $300s quite often. The viper series is my personal favorite in terms of overal quality and bang for your buck, but I would not hesitate to put a diamondback on a rifle for anything that requires shots under 500 yards.
My 2 crossfires sit on 22s due to the shortcomings I mentioned above.