I'm a Star Alliance FF but I have to travel from YUL to BKO and the price for Premium Economy with AF vs Standard Economy with TK is the same. Not to mention the significantly longer travel time with TK. So I'll have to break my allegiance.
Nonetheless, I have a 10,000 Skypoints balance from my previous escapades with Delta, but I was wondering if I'd be better off signing up for Flying Blue. I don't anticipate flying with ST anytime soon.