Since you've already accustomed to Garmin, then just go for its newer models. Fenix 5 is probably their best model right now. Awesome battery life, great fitness functions overall, a few smartwatch capabilities and simply a beautiful watch to wear for casuals. Drawback is probsbly the premium price.

I'm currently using Samsung Fit2 that looks just amazing and cheap. Unfortunately the battery suxx. I do love that it can snyc with my phone seamlessly which was why I bought it in the first place.

My wife uses garmin vivoactive 3 music because she likes to listen to music while running and that model fits her needs perfectly. And she won't stop gloating about her battery life over mine. But I hate the display on garmin with its low res interface, but I suppose thats why the battery lasts a long time.

Xiaomi and the likes are more suited to entry level fitness users imho. But if it fits your requirement, then go for it. But if yiu can afford it, I'll still recommend Garmin.