This is a cool question and should be discussed more at length, for this reason when I resort to seedbanks I always get regular seeds, with the intention fo breeding out these babes to my latitude, on this blue planet ..depending on the % of sativia, I go with 2-3 grows before the seed/plant is acclimatized to your area, my normal seedbank refuses to sell his Nanan-Bouclou (100% sativa) to any one not near the equator.
(
http://cannabisseedsforsale.com/product-detail.aspx?Cat=Southern Star Seeds&Prod=Nanan Bouclou)
so I took it upon myself to try a local grower who got the seeds from a buddy in FNQ, and was able to try later in PNG, the latter was mind blowing to say the least, same seed, same external soil grow, different location, I can only assume the same issue happens in locals as the UK, etc, at 65 degrees north trying to grow a sativa outdoors, hence the popularity of Indica breeds in the 45 - 65 latitude, then to confuse it more... ruderalis(autos) at the same latitude,
this has been a lost subject since indoor grows have become so popular