I'll chime in as I've been very mixed on my Streakflys. I picked them up at the tail end of 2022 and thought they'd be good for 5k races, tempo stuff, and maybe even some faster easy days. The first 5k I raced in them was night and day from my Vaporflys: my legs felt shot at halfway and I was jogging the last mile and my legs felt totally spent. This was weird because I'd use them for some workouts and they could actually feel almost too spongy on the track. Eventually I shelved them but started using them again when doing really fast stuff with long warmups. They were solid for this but could still be a little unstable because they're higher stack and the foam is so soft. Recently I've all but retired them but occasionally take them out for hills and even the odd easy run. For this they've been solid but I have better options.
Overall, I've got just over 150 miles out of them and still don't exactly know what they're supposed to be used for. They're not a racing flat, they're not a super shoe, and they're not even a Peg Turbo-esque hybrid shoe with super foam.