Recommended yes, required, not necessarily. Page 12-5 of my owners manual states:
0W-20 synthetic is the recommended oil for optimum engine performance.
*: 5W-30 or 5W-40 conventional oil my be used if replacement is needed but should be changed to 0W-20 synthetic oil at the next oil change.
I raised the question because I asked about oil at the dealer and was told the car had plain old dino-juice and I could change to synthetic after the break in. That did sound kind of odd. In any event I'll call Subaru tomorrow and ask the question, what type of oil is in my engine??
With all of this said I just looked at the maintenance schedule - states the first oil change is at 7,500 miles and thereafter every 7,500 miles. Must be synthetic. Guess the sales guy was not up to speed on the more technical side of the car.