Quarterbore,
I definitely reload. I have neck turners, flash hole deburrers, wilson dies and arbor press in several calibers, etc. The 300 Whisper, like you said, does look like fun, I forgot to ask about comparative bore life between a 300 (subsonic)and a 223.
Last, this guy sells awesome custom barrels with excellent, accurate chambers in a wide selection of choices. Chrome moly same price as production TC barrels from midway, but full custom in every way (polished, .0003 bore diameter tolerance, stress relieved, etc).
Hope this helps.
www.coyoteguns.com