I used the kit lens for only about 3 months before I got something else. IQ is good enough, other lenses I've had are only marginally better in IQ, however, there are many advantages when upgrading. No 1 is build quality, also the rotating, noisy element of the kit lens is just horrible in my opinion. Other advantages are USM (fast and quiet autofocus) and larger apertures.
If you feel fine using the kit just keep shooting with it, you won notice any big improvements in your photos after upgrading. If you want something that feels better in your hand you have many choices.