If you could hear SymX cover one song....

Fuckin' A! To all of the above! Good calls on the Zebra, Blondie, and Genesis! Yeah, TFOS would be nice!

More:

The Cars - "Moving In Stereo"
Siouxsie And The Banshees - "Overground"
Siouxsie And The Banshees - "Fireworks"
Blondie - "Accidents Never Happen"
Queen - "Princes Of The Universe"(staying dark- without the major key change "gay" part.):Shedevil:
 
"Song for America" by Kansas would be kinda cool. "Rediscovery (part II) - The New Mythology" reminds me of SFA a little.

Also "The Musical Box" or "Firth of Fifth" by Genesis,
"One of these days" by Pink Floyd?
 
The Cure - "Just Like Heaven"
Pet Shop Boys - "East End Boys"
Thin Lizzy - "Jailbreak"
Elton John - "Tiny Dancer"
Kate Bush - "Running Up The Hill"
 
I would definitely like to hear them cover ELO- ticket to the moon. It's a brilliant song in it's own right, but would be great with some romeo guitars and russel allan's vocals.
 
Kim Carnes - "Betty Davis Eyes"
Kenny Rogers - "Ruby (Don't Take Your Love To Town)"
Lionel Richie - "Penny Lover"
The Police - "Don't Stand So Close To Me"
'Til Tuesday - "Voices Carry"
 
MetallicA - Creeping Death

or

Megadeth - Holy Wars ... just Holy Wars ... they can probably do something to make up The Punishment Due ... don't really like it.
 
The Sails of Charon-Scorpions
Michael Romeo could do something very interesting with Ulrich/Uli Roth's solos, and Russell's vocals would make it even more powerful that it already is.
I can't think of any other band that would do the song justice.
 
Hullo guys im new here
now...
i think i would wanna here SX do:

1. Metallica - Dyers Eve
2. Pantera - Cemetary Gates
3. Yngwie Malmsteen - I´ll See The Light Tonight
4. Iron Maiden - The Clairvoyant
5. Angra - Running Alone
6. Dream Theater - A Change Of Seasons