I found the aftermarket barrels shoot better than the factory(depending on make). You can shoot wad cutters in the original barrels if you give it a good cleaning after each shoot. You might get stoppages in the feeding department with the SWC because of the shape of the bullet.
I have been there and dun that...
My 19+ year old Glock 21 has shot many rounds of lead SWC.
I could fire 100 rounds of lead without a major leading clean up.
My solution is to shoot PLATED AMMO. It is lead that is electro plated, so it does not lead the barrel. It costs a little more but, is worth the extra money!