[78w72]

the chances are very minimal that the cam is actually bad from how you said it was run. there's a greater chance the cam is fine, at least if you ran it to the break in RPM/time asap after knowing it ran right. just a suggestion to at least try & break it in right but its your engine, money & time so totally your call.

also dont forget that if you do change the cam the lifters should be changed too, you cant or at least shouldnt try to run what are now used lifters on a new cam, you didnt mention the lifters in either of your replacing the cam comments so just want to be sure you know that. also before pulling the old cam it would be a good idea to confirm with RA if/when another MPC1 cam will be available, it says out of stock & with the recent cam core shortages there may not be another one available for quite some time, plan accordingly or look into another brand cam.

that MPC1 is barely even a RV towing cam for a 400, would be a perfect time to consider another cam. comparing the stock cam to this one doesnt really address that a bigger cam, although still considered "small" with way more vac than needed for power brakes etc will perform better & still run very tame for a low comp street engine. not suggesting a big race inspired cam, just something more than a basically stock MPC1. these small stock cams were intended for emissions & MPG etc, much better "modern" cams out there.

best of luck on whatever you decide to do.