hmm I've built Sig, GP and Top Flite. Haven't had an issue with any of them and all three have given exemplary customer service when I've contacted them with questions or concerns.
The only thing I noticed was perhaps the advertising wasn't always accurate with words like "minimal carving". Imagine that, advertising not giving exact details, but other than that ......
My first Goldberg kit is on order (when they finally come out with the Sukhoi). From what I've heard I'll enjoy building from that company too... hopefully
Bob aka Nuker