I had an Eos 400d with the non-IS lens and now have a 550d with the IS lens.
The quality is better with the IS lens, but to be honest you will take ages to get to the kind of standard in your photography where you will be criticising image quality between these two lenses above composition/exposure/colour balance....you could go on.
Forget the so-called 'significant' quality upgrade between the two because it's only significant if you are really looking. I would suggest that you just get stuck in with what you've got and enjoy.
Btw, if you want to extend your range, save up to get the Canon 55-250mm lens rather than saving for the IS 18-55....it's loads of fun (although not as much fun as the Canon 10-22!)
The quality is better with the IS lens, but to be honest you will take ages to get to the kind of standard in your photography where you will be criticising image quality between these two lenses above composition/exposure/colour balance....you could go on.
Forget the so-called 'significant' quality upgrade between the two because it's only significant if you are really looking. I would suggest that you just get stuck in with what you've got and enjoy.
Btw, if you want to extend your range, save up to get the Canon 55-250mm lens rather than saving for the IS 18-55....it's loads of fun (although not as much fun as the Canon 10-22!)

