Matt,
I haven't used the Ultras but I have been using the Altitude IV WP regularly for the last couple of years and they have held up beautifully. They are the only boots I have had that did not need to be broken-in.
Dodger.
P.S.: I also have the HiTec Outlanders and whilst good they are not as good as the Altitude IV comfort wise.
P.P.S.: Just saw the date on your post...
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