The number of people in this thread who don't understand RSU grants at all is kind of shocking.
You're granted $800k of RSUs up front at the current stock price, 25% percent vests every year. That is VERY different than buying 200k of stock every year because the 800k is all granted at the INITIAL price, whereas buying 200k every year buys stock at the CURRENT price.
If you could take 200k cash every year and then time travel back to the start of the period with it and buy the stock, THAT would be equivalent to RSUs.