VoC: It has solar damage and it's pretty accurate, also it's got the oracle killer perk so it's very handy in the Vault of Glass. It'll be very useful in Crota's end due to the solar alone. MMT: 3rd eye is useful in pvp and pve, once it's upgraded to its main perk it can be fired as fast as you can pull the trigger/button ( or whatever you press) ridiculously fast reload, accurate at long ranger it also has a larger magazine than VoC. This is my experience with both weapons, but overall it depends on your own preference.