In reply to Roberttaylor:
Have you seen https://www.outdoorgearlab.com/topics/climbing/best-mountaineering-boot ? The Boa lacing system seems to be a concern.
I think longevity of winter boots is a really important issue that doesn't get discussed so much because we all get impressed with great technology and cool looks of new models. It's odd that I have a number of different pairs of ice climbing and mountaineering boots that I've accumulated over the decades, all of which still get used ranging from occasionally to regularly, but none of them are "super gaiter" style. I'm probably reviewing one of the new Sportiva models for UKC this coming winter, so I was looking at my current Sportivas last night to try and remember how old they are. My Nepal Extremes are from 2000, my Trango S are 2001, my Trango Extremes are from 2006 and my Baruntses are from 2012. All are lace ups, not a single lace loop has broken, all except the Baruntse have had heavy use. Last winter the material on the back of the Trango Extremes started breaking around where the crampon bail must push against it and it flexes around your Achilles - that's after 11 seasons of extensive use. I don't think it can be restitched but so far Gorilla Glue seems to have fixed it! But while I was working out how to fix them I used my Nepal Extremes for a couple of weekend trip outs and 18 years on they still worked absolutely fine.
The G5s look amazing, but having seen a couple friends panicking at the start of ice climbing trips when the zip broke on their Baturas (happened a few times to one friend) and knowing the epic fights they went through with shop/distributor/Sportiva itself to get boots fixed or replaced - I remain a bit sceptical of integrated gaiter boots.