Is the 457 worth waiting for over the 455?
Yes! I have both and highly recommend the 457 over the 455
I really, really liked my 455 threaded varmint for about 3.5 years. Used it in matches, appleseeds, plinking and a lot of dry fire practice. Nowadays it is unusable sitting in the back of the safe. Bolt will pull out or jam up in trigger mechanism every 3rd or 4th round now, more on this later.
CZ knew they had problems with the 452/3/5 series and finally corrected them in the 457. There are six significant changes/upgrades for the 457:
1) adjustable trigger assembly without sear ball headache
2) 60 degree bolt throw operation
3) shorter bolt throw
4) traditional , easy to operate side safety
5) threaded bolt handle allowing aftermarket knobs
6) most importantly, a side mounted bolt retaining lever
1-5 are welcome upgrades, but #6 is critical for a heavily used rifle. CZ used the trigger mechanism to retain the bolt in the 452-455. You literally pull the trigger to move the bolt retainer bar out of the way to remove the bolt. Over a lot of rounds the bolt and retainer bar banging against each other start to chamfer which eventually leads to the bolt overiding the retainer bar and either completely coming out or getting halfway stuck and jammed. This is a wonderful thing to have happen in a match!
At other forums I have been scoffed at or rebuffed or outright told that I induced this fault by ignorantly setting too light of a trigger pull in the factory stock trigger. Trigger is set at 4.25 lbs, definitely not light and inspection has revealed the contact points of both bolt and trigger bar have chamfered from impacting each other. I am not babying the bolt when running it, but I do not abuse it either. Confirmation for me that this was a CZ design issue is that I have personally run across 5 other 455 owners who have or had this problem, two of which had aftermarket triggers with the same issue.
Common data point is that all of us have a large number of rounds through their rifle. I have about 4 cases of ammo through it and about a third more cycles in dry fire (the action is pretty smooth when it works). If you are not going to use it a lot, you probably will never see the bolt pull-out problem, hence the scoffing from the squirrel hunting crowd as they more likely won’t shoot more than a couple bricks through it in their lifetime. CZ corrected this problem finally with the side lever release on the 457. I intend to have a side release installed sometime in the future , I still like that rifle.
