stick with GDAE--well, GGDDAAEE--unless you have a specific reason for something else...everything will go much smoother, tunes will make sense to your fingers and your fellow musicians, and all will be harmony and light everlasting... some mandolins are strung with a wound G and a plain steel string tuned to the G an octave up in the first course, ditto for the second course but with D. Gives it that twelve-string effect. Nice for those old Martin A-Style mandos. A folk thing, not a bluegrass thing.
A tuned mandolin is a welcome addition to any party...
Willie-O