I would say yes since she can get you some good items. I personally like that she gets you Super Effective berries. Those can be helpful in battle and are not easy to find. She also gets you things like a Focus Sash & Choice Scarf. Awesome. You might not like the Repel or potions too much, but she gets them for you only once.
In a nutshell, yes it is worth it. She will get you bad stuff at first, but the more you save, the more awesome the items become.