I have the two pairs of the 2025 Hyperflex Carbons and two pairs of Premiere Fields. Heres my take:
Hyperflex Carbons:
Superb fit. Right when I put them on and lace them up it's like a glove. No hot spots, just pure comfort. Glad that they ditched the sock like tongue for a traditional one. Super stable. I do wish it had one more spike underneath the toe area, though. Tough to keep clean. The Carbon model is more of a solid material versus the standard model's mesh-like material, so the lower half of the shoe is easier to clean. But, the upper parts are difficult to clean (the tongue and inner/outer part of the opening). I've come to a point where I just don't even try anymore (this is the white pair I am speaking of). The black pair doesn't show as much dirt.
Premiere Fields:
I know you are looking at the Packards, but I imagine these will be similar in terms of fit. Comfort wise, the Hyperflex win all day for me. That's not to say that the Premieres aren't comfortable, they just take a little longer to break in and "mold" to your foot. I've worn my pairs 6-8 times and it still takes a good hole or two before they feel "fine". After that, maybe an occasional hot spot that fades away after a few holes. Stability with the spikes and traction are second to none. However, they are low cut so if you need ankle support, these aren't great for that. I would never walk the course in these. Very easy to clean these but I typically only wear these on dry days or when I am playing a nicer course/club.