*presuming some level of inflight service/amenities to distinguish D1 from F* … if it’s just me, I’d probably opt for MSP
for a group or family, I’d vote for the cost savings and book via SLC … the risk being a schedule change *not* meeting rebooking criteria (departure or arrival time change by 60 (90?) minutes, or an impossible connection) that switches SLC-HNL to a 75S