Are there any benefits to this over a...
Are there any benefits to this over a standard keylock biner? Weight seems to be the same. Cost maybe?
The biggest benefit of a wire gate is the lack of gate flutter. Because solid gates weigh significantly more than wiregates, if the biner knocks against the rock, the gate will flutter open, and there's a small chance the rope or something else will pop out of it. Wire gates have little inertia, so they don't flutter.
The other main advantage besides what James said is that these wont freeze closed when you are ice climbing like a solid gate biner may.
@ James Jenden -- I'm not sure gate flutter has really been shown to be a problem. Gate flutter seems to be more of a modern rock climbing myth in my opinion. If you disagree, I'd like to see an example where gate flutter/chatter has resulted in a longer fall.
See the link for a discussion of the myth.
@ twop -- I think the real issue with gate flutter is not that your biner is going to completely open and unclip from the rope, but rather the seriously reduced strength of an open gate. You take a huge fall and by coincidence the biner smacks the wall at just the right moment and opens the gate just enough to disengage the lock/clip/keylock/whatever-you-have, and 8kN (1800 lbs) is much more likely to fail than 24kN (5400 lbs).