Just out of curiosity, what cams are you looking at? Most 360 mag roller cams I have found for the magnums are either racing cams or factory stocker replacements, nothing in the mild-med performance range - as far as I have found...
On my magnum motor I run a comp cams, it was in my 360 and then I put it in my 408, its not to radical but drives pretty nice. the specs are like .528 lift/.536 exhaust, close to 220 duration on a 114 cl with 4 degrees advance ground in, I installed it at 4 degrees advanced too. This is in a FI truck too.