Based on the issues 2014 (and even some 2015) Forester XT owners have had, I'd suggest waiting until at least the 2016 MY.
I've personally experienced hard/long starts, as well as one instance of missfiring, both of which seem to have been fixed by two different ECM updates.
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Instead of looking at this as turbo vs non-turbo, I'd look at this from a HP and performance stand point. You're not comparing two differently-sized engines, one turbo and one not, but making the same HP; you're looking at a performance model and a non-performance model.
Most performance variants come with a reliability trade-off. For Subaru, that trade-off puts usually lowers its reliability rating from excellent to average. That's a fair trade to me, but that's because I really, really enjoy the difference between the turbo offers.