Just my opinion but...there's an awful lot of people making a decent living selling parts that aren't REEEEALY needed but just look cool or someone saw it the pits on a Pro Stocker or something. Hey, I'm a devout capitalist, and everyone's free to spend their money on whatever they percieve a need for.
Not that I think GM is ALWAYS right, but they were never in the business of deliberatly building unreliable cars and went/go through GOBS of money to R & D the most reliable parts possible (admittedly for the cheapest price) so as not to get a reputation for building LEMONS. I have a hard time believing that relocating the coil off of the HEI cap makes any significant difference in longevity or performance of the system. If it did I suspect it would have been built that way in the first place. Again...Just my opinion.
'69 Garnet Red Convertible, Ivory over black, 350 w/turbo 400