A Riva is an ego. There's the ego, igo, kgo, etc.
The Joye ego is regulated. Lower voltage but a consistent vape until the battery needs to be recharged. Other models have a hotter vape but shorter charge life & consistent reduction in voltage over time.
I've used and like the joye ego. The other versions weren't out when I started vaping. But many people do prefer the higher voltage of the riva, kgo, etc. If you prefer low resistance cartomizers, you might prefer something like a riva, kgo, etc.