I have the CZ455 varmint. I was lucky I got a "good one". I have heard of some that don't shoot well. I can easily hold a 0.5" 5 round group at 50 yards. That is more than good enough for my needs right now. I ended up going with boyds stock with a cheek riser. Love it...but I estimate I'm in the gun for about the same you are looking at. So, in retrospect, I probably would have done well buying the one with the Manners...
Depending on how risk averse you are, I think the Tikka T1x will likely have better probability of being a good shooter out of the box and better fit/finish. Slip it into a KRG chassis that is very adjustable (for about the same price of the setup you are looking at) and you will have an amazing rifle. Of course, this is coming from someone who has the CZ and wants the Tikka too.