I use a CGW 11.5 mainspring and have never had a light strike on the primers, BUT I use nothing but Federal primers and change the mainspring 2 a year.
I know this isn't the St. Louis area but I've had 2 handguns done by Accu-Kote in Claremore Okla. Both guns turned out very nice,PM me and I'll give you email and phone numbers if your interested.
I have found that the 11.5 spring will light CCI and Winchester primers until you get to around 3-400 rounds then it gets kind of iffy. Federal primers go boom every time.