Tried i4's, very comfortable, good breathability and nice and light. Only problem is the size: It varies between people, but when I opened my mouth wide to shout my chin would stick just a little bit out the bottom and my jawline was just barely covered.
The great thing is that the Vio's pretty much solve most issues that I have with the i4's. I actually tried on a pair last week and they're very comfortable, lightweight and breathable just like the i4's but they're also give quite a bit more coverage without sacrificing any of that.
Out of the two I would go for the Virtue Vio
The KLR's seem pretty good but I don't have any experience with them. I suspect they'll be very similar to the Vio's though.