What is a good IR?

What is in your opinion a good Install Rate for mobile banner ads?
I am achieving 0.30% - 0.55%, is it low?

And the second question is:
Why should I really care?
I mean, it’s a thing that I don’t really get about this advertising model… I should make the worst possible banner, instead of the best banner, because as soon as I pay for installs, it’s better to pay for absolutely SURE users… if I put a very appealing slogan there’s the risk that I get higher IR but a less centered target of users, because I get also curious users with no real interest in my app, what do you think?

I guess the higher CTR you got, the cheaper installs you can buy. That would compensate the fact that you would get “impulsive users”. Think about it, which ad company would like to show ads that do not sell? it is a bad business for both developers and ad companies.

Not really, I pay for “installs”, or at least this is what it says.
I pay 0.20$ for each impression that is clicked and that leads to an install.
Over 100.000 impressions I have around 5% of CTR, and 0.5% of IR.
If I pay for Installs, I am wondering which advantage I have in making a good ad. A bad ad is much more effective, as it brings me oonly really interested users.

I know what you mean, you pay for installs. But what i wonder is if you will be able to get the same $0.2 price the next time/campaign. A bad ad might be good for you, but is definitely bad for developers and ad companies.