I bought this AIG Sapphire Enhanced Plan 1 for more than 5 years already via my family agent from AIA. She handles the claims process for my family and I and has always been very prompt in ensuring everything is prepared for us to submit the claims.
After she's done her due diligence to submit our claims, the response from AIG is always very fast. Just recently in July, due to an A&E visit, the claim submitted took less than a week to receive a response from AIG directly and the payment to my bank was done in the following week.
AIG has been pretty encompassing in terms of the reasons for our claims. I've filed claims for a sprained ankle during running, A&E visit due to a bee sting, and other related claims due to leg injury and all of them are claimed successfully.