Sounds like you already know that going out with her would essentially be using her, roz.
Certainly if the impetus is to "get over someone else." Not only does that not work, it's just not a nice thing to do to anyone.
As well, what a relationship "is like with another girl," is going to vary depending on EACH girl. A relationships with this girl is going to prepare or inform you no more for relationships with other women than a relationship with any random boy would.
If you want a very casual relationship right now, for the reasons above, despite the fact that they're pretty dicey, I'd say this: can you tell this girl all of these things right out comfortably ("I don't like you ALL that much, I really want to get over someone else, and I'm curious about dating girls and figured I'd start with you simply because you're available to me,")? Do you think she'd still want to date knowing all of that? Could you even tell her all of that?
If not, you've got your answer right there.
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My epitaph should read: "She worked herself into this ground."
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