It’s not at least as good as stock, it’s worse in most markets. Because your stock is appreciating before you’re allowed to sell it but the cash is depreciating to inflation.
It's a free call option on the stock. If it goes up you keep vesting at the new stock price which might be way above market rate for you position and if it goes down you get refreshers at the end of the year to bring you back to a market rate salary.