I have also degree'd several cams and about 20% of them come out within 1 degree which is about as close as you can get it. Your right there are a lot of variables and just because a timing set is labeled a true roller doesn't mean anything either. A couple yrs. ago I rounded up 5 different timing sets that were true roller's and only 1 set (Cloyes) was within 1 degree. The others ranged from being off by 2 degrees to as much as 5 degrees.