Will Iphone 5 be slow on IOS 9?

So my friend is selling me a Iphone 5. Not a 5c or 5s.Basically Iphone 5 is the same as 5c.Anyways he selling it to me for a good affordable price and its in very good condition. But IIm scared if I end up buying the iPhone and ios 9 comes out, my device is going to be very slow! Because before I had a Ipod 4g and when I updated it to ios 6, my ipod became very very slow and crashed on every app! I tried restarting it and it was still the same.Basically my ipod became very useless and I had to end up getting an android phone. But please I need help! I don't want to make this mistake and waste my money!

Hell, yeah.

It will be a little slow, but not as bad as the iPod. The iPhone is a lot more powerful.

Of course we wouldn't know until it is actually released. The closest thing to finding out would be through downloading the iOS 9 beta & running that to see. Though it shouldn't be since iOS 9 was made with optimizations in mind for older devices hence why the thought to be retiring iPhone 4s still will get this update.