Most of the LPKs I've bought in the last several years have had good quality FCG parts. I'm talking about "known good" parts makers, like Schneider hammers, etc. That is not to say that all of them have "felt good" when first assembled... But if you employ due diligence and clean the crap off of the parts before you install them - especially the hammer and trigger - and lube the hammer and trigger bores before the pins go in, the stock trigger isn't awful. I haven't been worried about coiled pins versus standard roll pins because I have never had a problem with standard pins, but I suppose they are nice.
I've never had a "problem" with any LPK, though once I wound up with a part missing from one - the vendor sent the replacement part as soon as they got my email and I had it in a couple of days. I only use kits (or FCGs) that have standard, rounded hammers. Notched hammers aren't only bad for .22 kits, they suck with 9mms as well (and no, that "9mm hammer" isn't "the way to go," either).