You can try popping in the Verizon sim but some folks have run into issues without officially unlocking the device. Even if it's a CDMA based device, most Samsung devIces require the unlock code when switching carrier's . When you say "Metro", am I correct in assuming Metro PCS? I was able to find some info that might be helpful. MetroPCS® Phone Unlock Policy - MetroPCS®.com
If this doesn't work for you, or you're with different "Metro" carrier please let us know and we'll try some other options.