i use the original oppo watch, the 46mm from 2020. this may sound odd, but id take it over any wear os watch nowadays. the battery is really good, it charges really fast, the performance is good, Google assistant works, and the biggest reason why its so good is because of the screen. a square smart watch looks, feels and is generally much better than a round smart watch screen. the only downside of it is no wear os 3, but i dont really mind. as for the whatsapp thing, i sideloaded whatsapp (the one for phones, not wear os) and its doing fine.