As soon as your RSU vests, you can sell it for cash. Most companies offer an auto-sell option that works even during restricted windows. With a good vesting schedule, it's almost identical.
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.