Which heads wpuld be better?

Ha ha ha I was out looking around and found this. http://www.hotrod.com/howto/113_0304_junk/index2.html
I would say that if you performed a sound short block rebuild, then the rest of the copy should be fine. There not really potent as in inducing heavy stress to the internals but then again, beating on a stock engine everyday will show shortcomings.
Weather it's the Comp Magnum 280 cam or the XE268, it should prove itself very nice to drive in the street.