I would like to echo DD4LIFEUSMC's response. I had the same question when I bought my handsome CVA Optima V2 pistol. Sabots are too pricey for me even in bulk. I tried patched round ball and they were just OK, I'm told because of the fast 1-28 inch twist (I don't know enough to say yes or no to that though). I bought a LEE 250 grain .50 caliber R.E.A.L. mold and using pure lead from roofing materials, cast a can full of slugs. They have been accurate for me and do well with light to heavier charges. When they hit the cardboard backing of the target they sound like a 2X4 slapping a side of beef. They are to me, a wadcutter design. I'm in the process of rolling paper cartridges for my CVA using them and a waxed felt wad I make. I do not use a sabot, and with a 2X scope at 40 yards have gotten some 1 1/2 inch groups on a day so cold most of my time was spent with my hands in my armpits.
#209 shotshell primers here in Southern KY are cheaper than percussion caps, and with lead at 65 cents a pound from the recycler and virtually no wastefrom the roofing material, my biggest expense is for the Triple Seven propellant (which here is cheaper than black powder and available at Walmart in season).
As to the popularity of inlines here, I can say that inlines are an evolutionary thing not to be shunned. If they were, then a group could also shun revolvers and percussion caps as not being in keeping with the traditional spirit of flint guns, which are not in keeping with the traditional spirit of matchlocks, etc etc. I love my stainless CVA AND my Ruger Old Army's. I'm sure my great great great Grandfather who received a2000 acre land grant in KY for his service to the new USA during the Revolutionary War would have snatched my CVA and 209 primers from my hands had he the chance, and thanked me for the thing.
It's all powder and lead. Don.