175K miles is barely broken in for a subaru, shouldn't be a problem, you'll want to make sure the timing belt is changed if the lot hasn't done that. Since it's an auto, take it in the lot, cut the wheel as hard as you can and drive it in a slow, sharp circle. If it shudders and bucks around then don't buy it unless you don't mind replacing the fairly cheap/easy to find transmission. Or are willing to take the chance that you can fix it with a flush and an additive. Manual's are more fun and problem free. Just saying.