Ed, they run good when you get a good one.  On my ASP .91 the carb barrel cracked from the clinch bolt.  I do not think I over tightened.  The metal seems very soft.  Repaired it by straighting it and putting glue in the crack.  Had a similar proble when tightening the trottle arm on the carb barrel of a Magnum .30 four stroke.  The metal seems very brittle.  The only engines I have this kind of issue are Magnum and ASP.  It could be coincidence, but that is what I form my opinion on.  No such problems with Fox, TT, OS (long ago), and others.