I have three CZ457s - an American, Varmint MTR, and Varmint Precision Trainer in the Manners PRS1T stock. I fell in lust with the American's appearance after seeing the initial advertisements for it in 2017, and the MTR's stock plus the match chambered barrel had a strong appeal as well. I have a one-man gunsmithing shop & ffl, and finding an American was easy, but it took a few months before I was able to find the MTR. The American didn't shoot worth a hoot, even after pulling the OEM bbl to recut a precision 11* crown (factory crown was fugly & ragged), but I kept shooting it due to the CZ fans over on RFC saying it sometimes takes 1000rds before a factory barrel comes around. The MTR OTOH, shot really well right out of the box, and adjusting the trigger for a break just over 1lb made it easier to shoot decent groups at 50yds with it.
Eventually, I decided to re-barrel the American instead of selling it off. Reasoned that I really liked the appearance of the factory sporter stock and the very smooth & reliable function of the action. I bought a Shilen ratchet in #5 contour, parted off the 1.20" shank, and turned the transition radius down to a tenon that was a nice snug fit in the action. Cut a match chamber with my EPS reamer, then milled the extractor slots, set the headspace at .043", and glued it into the action with Loctite #609. That got me away from having to cut the deep grub screw seats, and eliminated the stress on the action & bbl that grub screws create. That rifle now shoots as good as it looks (maybe better), and I'm very pleased with it. No, I don't shoot it in competition, but it's just what I was after in the 1st place - a classy looking sporter that's very accurate.
I decided to buy the VPT because of the appeal of the Manners stock - I have three V22 repeaters in PRS1T stocks, so obviously like that stock. However, the factory 24" bbl had issues, though it did shoot considerably better than the American's factory bbl had done. I put 500+rds through it at 50yds, and felt that groups had improved a fair amount since new, but when I took it out to 100 & 200yds, it fell on its face - couldn't even keep 10rds of a known good lot of SK Rifle Match on an 8" gong at 200. So another Shilen was ordered - this one a straight, no taper of .860" dia. Repeated the same process that I'd used on the American's Shilen, and wound up with another very accurate rifle.
So, in my experience, two out of three factory CZ barrels were really unsatisfactory, and had to be replaced. I don't know if CZ has improved the quality of their barrels since I bought my rifles, but have to wonder about that, with the current positive posts in this thread claiming good accuracy out of the box. I've been happy with the fact that CZ designed the 457 with a fully adjustable trigger - not many companies seem to have the courage to sell a design that allows owners to easily tune their triggers, especially in today's sue-happy society. I wouldn't have spent the time or money to re-barrel the two 457s that needed better barrels if I didn't really like the action. Granted, my experience with custom barrels that I've fitted & chambered on 22RF rifles I've built for myself (Stiller 2500XR, two CMP 40Xs converted into repeaters by Jelrod, three V22 repeaters and two V22S single shots) raised my accuracy expectations & standards to a level that very few factory repeaters in the 457's price range will ever achieve. But like I said before, I like the 457 action, and applaud CZ's efforts to bring a quality 22RF rifle to market at the price point.