the benefits of the magnum head: closed chamber, good squish characteristics, fairly decent flow for what it is if you keep the cam reasonable enough to take advantage of that aspect. 1.7 rockers, updated valves & hardware over the 360 stuff.
if the 360 heads needed any work and the mag heads were more ready to run or needed less $$ to get them on there i would say they would be the better choice-- depending on the nature of the build.