Got this in the old-timey analogue mail on Friday, for my Edge that actually gets a decent amount of use. It runs 05/12-05/03.
Conveniently, I'm starting a two-month US/Canada trip this week. I got the Prestige a couple of months back but they stopped posting my points after I switched to Citi Rewards then the agent tried to send my handful of straggler Qantas points (which I'd been willing to sacrifice) across. I'm hoping they'll fix it but if this comes through the Edge will be even better where Amex is accepted (which is almost everywhere worthwhile except Costco, in the US):
3.0 MR (3.0 KrisFlyer) > 5.0 Citi (2.5 KrisFlyer)
raw Amex forex rate [better than] raw Visa forex rate
3.0% forex fee [better than] 3.4% forex fee