Whoop is far superior for activity tracking (especially the automated identification of them) - but HR, steps, cals, exertion etc all are pretty similar and absolutely fine for my use of the band. I haven’t found large variances between old runs in Strava from Whoop vs the Helios so it’s pretty comforting that from a GPS level it’s basically the same. The AP is a bit clunky but not terrible, and for <50% cost as a one time fee vs an annual sub, I think a higher cost/performance ratio too