RemMan,
Let's keep this simple. I think $100 for a Encore barrel is a good price, no? You probably handload, yes? 358 WIN brass is readily available via necking up plentiful 308 WIN brass, or by Hornady. The 358 WIN does well w/ bullet weights from 180 to 225 gr. or 250 gr. even. I favor Barnes 180 & 200 gr. TTSX projectiles. Velocities close to 2900 fps w/ the 180 gr. & 2750 fps w/ the 200 gr. This is from a Hawkeye 22" barrel. Recoil is not bad at all w/ a Limbsaver recoil pad. I'm now working up loads for a 20" barreled Ruger American. You won't see much velocity loss from the 18" barrel. You would have a great elk timber rifle or deer setup good out to 2-300 yd., easy w/ a 1-4 or 2-7 X scope. And you can shoot the same pistol bullets from your 357 for practice reduced loads. i don't see a downside...
Have fun,
Mark & Belle