Man, is this a topic of frequent debate!!
Ask your friend for link to his source of information on these cases where reloaded ammo was an issue in a self defense event. There may be some, but I've not been able to find one, nor has anyone been able to provide it.
Having said that, I carry factory ammo in my defensive guns for a number of reasons. Mainly because I can't load anything better. Yeah, my hand loads are reliable and powerful enough, but with the powders/components available to the industry, performance can be optimized. It's a small edge I know, but an edge just the same. Then there's that little legal matter of hand loads vs factory for personal defense. I don't think it would be an issue, but I'm a cautious man. Like a previous poster, I find the cost of a few boxes of factory ammo insignificant compared to the potential legal costs involved in a civil case.
Reloads can be tailored to closely duplicate bullet weight and velocity of the factory stuff for practice purposes.
Savage