Please spend a lot of time researching this subject for your specific motor. Go to a Subaru forum, figure out what motor you have. Some Subaru's have headgasket problems, they have an additive to use with coolant changes, if your type of engine is supposed to have it added, please ad it! Or you will have issue's later down the line. I would just use the Subaru coolant If I was you. Pentofrost A2 would be your other option.
08 Tribeca 82k PUP 5w30 wix
06 Accord Hybrid 131k PUP 5w20 wix
02 Chevy k3500 97k Delvac 1 esp 5w40 wix
00 F350 133k Delvac 1300 15w40 wix