75 Dart - 340 - Header's Choice's

Maybe I got a bad set, but I have a set of Hedmanns that have only a few hours on them and they split at the collector where the primaries come together. I called Hedmann today and they said they will replace them but I'm not sure I want to go through the trouble to have it happen again. IF it was my fault, I'm wondering if I didn't have enough flexibility in the exhaust system or my mixture is lean..but with them being basically brand new? I don't know. Just putting my experience out there for consideration or to see if someone had the same happen to them. Not happy.