340 Engine Shake

Google Comp Cam lobe, and general quality issues.
I won't use anything Comp anymore .
is it lifters or cam that the problem ? Damn putting the engine in my car next week or so . and it is a Comp cam . So far broken in on the dyno and several pulls all is good . Next week I'll know for sure after a few 100 miles of driving will not be pleased if the cam goes bad . Don't think this is limited to Comp cams , industry wide problem