[amsat-bb] mast material question

I am awaiting delivery of a Gulf Alpha dual band antenna that I plan to mount on a single mast for azimuth-only control.  I've read various reports of metal masts causing polarity (?) issues and others that say they are ok as long as you don't align the elements with the mast etc...

So - what is the real scoop.  Should I be concerned with mast material with the above setup or is a traditional metal mast fine?  If not, any recommendations would be greatly appreciated.  The stronger the better IMO.  Although I realize there is a pretty minimal wind loan, and it will be mounted in a Glen Martin 4' roof tower, I'd rather not worry about my mast snapping in the wind...

Thanks,

Zach N4ERZ