There's a difference between changes that come as a result of enhancement and new tech, and changes made because the original design was inadequate. It's not like their lifters predate the factory roller hardware or is offered as a budget item.
If comp was having failures, I'd call the original design inadequate. Especially since they supply the mating hardware (cams, springs). So all those comparisons above are apples to oranges.
If nothing else, I'd be telling the comp rep on the phone "so you FIXED the design, but want me to run with 14 of your shitty versions next to two that are fixed? Sounds like something other customers should be aware of and that I should look elsewhere for quality hardware" because that's the reality. With all the competition in the space, they shouldn't have to be convinced to make it right for the customer, especially when they're full of crap (Re: paint). I'd call back and hope for a different rep and see if that particular person didn't wake up with a bug in their rear.