I have done 14BFF disc conversions on lighter trucks. I really liked it. Not a big deal, saves weight, but I never did a lot of hauling/towing.

It seems to be that if I were do to one on my dually it would not have the same braking capacity (little rotor vs big heavy drum)???

Not sure but my truck came with rear discs. They work great. But pads are a nightmare to replace.

anyone else?

You talking about for your 87? I know a guy that sells conversions that use 2 calipers per side. Not sure if they are in production yet though.

My '03 came with disc brakes. They feel kind of week to me though.

Most of the really heavy duty diesel chassis like Freightliner still use drum brakes all around. My Pace Arrow motorhome on a Ford chassis had disc's all around and had lots of brake issues/problems, mostly with over heating. In 30,000 miles I replaced all 4 calipers, pads twice, wheel bearings and grease seals that melted from excessive heat. Oh, and 1 front tire that melted too.

Man, that would not be fun.

I can see how drums would be better - all the buses and big rigs have them that I know of.