The iPad and the Kindle are totally 2 different devices. If she wants a true reader without the bells and whistles, gift her a Kindle. I've read on both devices and the iPad doesn't come close to the ease of reading on the Kindle. The lack of glare, the readability of the characters, and the resemblance to paper cannot be matched by the iPad. The glare on the iPad is annoying.
However, if she wants a reader that can also do other things, then gift her an iPad.
It really comes down to what's most important to her: reading books or reading/surfing/games/email/productivity.
Personally, if space is an issue, I'll just bring my iPad. If it isn't an issue, I bring both and use the Kindle to read.