Greetings,

I am looking at an IAH-PVG itinerary and considering AC via YYZ as an option. The flights are:
AC 8108 arr 10:59 --> AC 87 dep 13:00 (2 hr 1 min)
AC 88 arr 18:45 --> AC 8115 dep 20:55 (2 hr 10 min)

I'm not at all worried about the outbound, since it's just a quick passport check from US to international. However, I am very concerned about the return. AC 88 is consistently 30+ min late, and I have never transited through YYZ or flown AC before to know the US preclearance procedures. Is a 2 hr 10 min connection safe? What would happen in case of a missed connection, waiting for US customs? This is the last flight to Houston for the day. Would you recommend this itinerary, or am I better off spending $100 extra to fly UA?

Thanks for your help.