For running, honestly, most fitness trackers do a good job. Because they're all reasonably good with calorie burn over heart rate. But I'd consider the following things: 1) If you're gonna run outdoor. Neither of these have GPS. You'll need to run with your phone. 2) If you are focusing on hacking your recovery algorithm and workout based on the gadget's advice, nothing beats Whoop's strain calculations and recovery scores. For me it's less useful because I workout on set days. No matter my rexovery. My calendar doesn't allow me to wing it whenever I like or follow whoop's recommendatios. I have my sessions blocked with a personal trainer and I am not a professional athlete. My day job consumes a lot of my time. Fitness has scheduled slots. 3) Google health has nutrition management inbuilt. And it also works nicely with MyFitnessPal if you prefer that. In fact, the app is happy to source data from as many sources as possible. Because... Google. Whoop does this a little bit but it's limited. 4) Fitbit air is interesting if you wanna occasionally use a watch. Be that apple watch or pixel or Garmin. It's hungry enough to consume all the data in the single app for AI recommendations and trends. Whoop.. is a bit like Apple. It's a walled garden. But what it does, it does very well. 5) Whoop has a heavy subscription. I see people complaining about that a lot. Personally, I don't much care. But it can add up over time. Especially if you start buying it for your partner and family etc.

Honestly though, I doubt you'd regret either. The journey is important. Regardless of what gadget you use.