I'm biting my tongue about the cams. Most of my issue is with all non custom cams. The quality of the SADI material is not really very high, even though billions have been made that way. The SADI cam material is a rare but pointed cause for some performance issues, cam failures, and engine failures.
The real issue I have learned recently is that almost zero OTS cams(not billet cams which are very rare OTS) have accurate specs as designed. Meaning that the cams almost always do not have the cam spec lift, duration, or valve events as designed. They are off a little bit, degreeing a cam is very necessary.. It's just hit or miss with the accuracy from that SADI construction.
A custom billet cam is basically perfect when it is cut, or else it is scrapped and another one made. The billet cam is also much stronger, does not flex basically at all until wildly high rpm's. SADI cams begin to flex at normal upper levels, like 6000 or so and more.
So my point about the cams is really the price and performance. The cost difference is very minimal considering how much the entire engine etc costs. If not for other reasons like a time crunch or that you have a cam in hand(no cost), or you will sell the vehicle very soon, the custom cam is a better choice. Regards,