I got a black 256Gb Flip 4 as a second phone. I put the white/orange Samsung silicon case on it. It looks and feels great.
It's an impressive phone, for sure. I didn't expect it to be faster compared to my iPhone 11 Pro but it really flies. Battery life is stellar (but I don't use it much, it drains about 15% during the day, which is excellent). The form factor is very good. The fingerprint reader is pretty good, although not flawless. I was impressed with how generally polished the Samsung apps were - last time I used a Samsung phone it wasn't that nice...
The negatives would be:
I get the orange dot on the external display even where there's no actual notification. Seems like a bug.
The external screen (which btw is awesome, great idea) just takes too long to get into notifications. Double tap => animates clock => slide to notifications. Pretty but a little slow.
Cameras are so-so. I think the main camera is perhaps a little more detailed compared to my 11 Pro but worse colors and too much processing. Obviously no zoom camera. It's not overall bad, definitely usable for photos, but not flagship level, clearly.
Also the speaker could be a little better.
I really appreciate the ability to use it for videocalls by folding it at 90deg, it can sit on the table. It's a great feature.
Overall, I'm so impressed that if Apple doesn't make a nicer iPhone 15 - and I mean something comfortable to hold in hand, unlike the current sharp edge, tacky stuff - I might jump ship.