I just got my Klim Havoc GTX boots, they were an anniversary present and I did not want to like them but I LOVE them.
Again, the Revit Discovery boots were perfect all last winter, waterproof, warm, protective and they are also my dirtbike boots with the BOA system and Outdry, easy-on, and easy off.
The Havoc are every bit as good with the BOA adjuster on the back of the boot as opposed to being behind the tongue on the Revit's. The boot as LOT more insulation than the Discovery's so they will be a lot warmer, which is a good thing, they are also beefier over all with a thicker sole with even better traction and even a siped sole like snow tires have, they are Michelin soles after all so I think they will also make great winter boots. All it takes to get them on and off are the big velcro flap to the outside of the side of the boot and the boots have every bit as much protection as my dirt-boots, maybe just a little less on the toe as compared to my Revit's but as I'm in the snow, I'm not worried about it at all.
The pictures everywhere online don't do them justice and I got the black. I'm not a fan of square-toed shoes/boots but the shape of the boots is fantastic. They are going to be keepers and will be lasting a long while as they will be my dedicated snow boots.