The Highway One Strat is an excellent guitar. Whilst there are individual differences between each guitar, there is a certain guarantee when you buy an American Fender. I will vouch for my Fender (which isn't even an American guitar) as a stunning piece of work. Another advantage to owning a Strat is that parts are incredibly easy to buy. I've replaced most of the hardware on mine in the year since I've owned it (as well as rewired it). It might be worth buying her a good guitar strap (wide leather) and a set of strings (get some gauge 10's - halfway between everything, I play much heavier, but my playing style requires that I really have to dig in).
Again, to reiterate, Highway One Stratocasters are EXCELLENT guitars. If she's already playing a Strat copy, get her the real deal.