Slagowski ran 49.04 FAT last spring, when his 800 was over three seconds slower and his mile was 11 seconds slower. Also, one look at videos of last spring vs. today and it is plain that he has matured physically. It is not a stretch to say that he is now capable of 48-flat (which is what his coach believes). Also, If you look at his even-split 1:48 in a low-key HS invite, it is almost identical to Brazier at this time last year. Clearly he is easily capable of 1:47 if pushed (no to mention that he is the indoor champion at 800m). Clearly he has top-shelf speed for a miler. Fisher and Hunter haven't gone sub-1:50 yet (probably capable of 1:49, 1:48 at best). The lines are pretty clear: Slagowski is a well-balanced middle-distance guy, Hunter is the distance-side miler (has a shot at Verzbicas' 2-mile record).
The question is whether they will meet up at Pre Classic or Brooks' PR. It's the closest thing to a Coe v. Ovett we will see at the High School level.