As I see it the biggest advantage of TTP over APEC is the fact that TTP is valid legal identification in Japan whereas for APEC you still have the legal obligation to carry your passport with you at all times. Now I'm sure many people visiting Japan don't carry their passports with them all the time but if authorities do want to randomly stop you and you don't have it on you they can definitely make it a hassle and I believe the fines can be 100,000 yen or more if they feel like pushing the issue.