Looks like neither will actually be available to buy for a couple of years (or possibly more), so I'm not sure what the rush is.
Just remember that the rule of thumb used to be that as a new plug-in EV model approached production, the price would go up and the estimated range would drop. Recently a few auto makers (GM, Tesla, Jaguar) have been much more careful to under-promise and over-deliver, but I wouldn't place any wagers on a brand-new company like Rivian doing so. Several people have expressed strong skepticism that Rivian can deliver this SUT for the price quoted. I'm certainly not going to claim their estimated price is impossible, but don't be surprised if the price goes up before sales/ deliveries actually start.
I certainly hope Rivian succeeds, and it does look to me like the company is being run in a way that seems to have a realistic chance of success. (Unlike, for example, Better Place or Faraday Future or Nikola.) But that doesn't mean I think we should accept all their claims as verified fact.
Still, I'm optimistic enough about the company's chances to say...
Go Rivian!