K and N's and smooth tubes a waste of money ?

[woodyz viper]

Wondering if anyone has done before and after testing / rw dyno of a stock vehicle with K and N's, smooth tubes done.
Past experiences I've had, bolt on's were a waste of money unless internals are done.

Exhaust is a definite, knowing I'm pissing the money away as the power gains will be minimal at best, but need the sound.

Wasn't sure if the K and N's and smooth tubes were just a waste of a few hundred bucks.

Thanks

[99 RT/10]

Depends on the car, but most ill pick up 10-20RWHP with tubes and filter. If you're looking for a set of K&N's I have a nice used set(need cleaning), I take $30 and you pay shipping