I haven't tried the Scarpas, but do have the Hanwag Alaskans. I've also worn out/trashed half a dozen other mountain boots, so I'll put in my two cents.
First the standard disclaimer: Fit is the most important thing and there is likely significant differences between the fit of the boots you are looking at.
Other comments: The Alaskan is on the light end of sheep hunting boots. If you have decently strong ankles and feet, they will certainly work. They will also cross over to other non-mountain activities quite well. Basically, they are a very very sturdy hiking boot. The big pro I see to the Alaskan's is that they are very light (4.3 lbs for my pair), which pays dividends when hiking long distances. The minor negative is the relatively low top They are also non-insulated, but I usually prefer that in a boot. The Hanwag is not a lace to toe design, and I have issues with the leather on the toe of the boot bending and hitting the top of my toes when walking. For that reason, I'm not going to be taking them to the mountains. As far as I know, I'm the only one with that issue though.
The Scarpas I tried on seemed like a much heavier, stiffer boot more suited to really rough country and long scree slope sidehills.
The biggest failure points I've found (in all my leather mountain boots) are the rands, seams, and sole/midsole.
A high rand will almost always peal away from the leather near the bend points. If you don't glue them back on, dirt will wedge into the crack and start pealing them even further away. It happens to all boots eventually and isn't a huge deal. My current preference is a relatively short thick rand that doesn't come too high up on the book but still deflects rocks. I like the way the Kenetrek Guide series of boots are set up in that way.
The other thing I look for in a leather mountain boot is minimal seams. Shale will eventual cut the threads and cause massive boot failure at the most awkward time, so I like as close to one piece as possible. I think it makes them a bit tougher to break in, but they last longer so it's worth it. Both the boots you are looking at are good that way as well as Kenetreks and Lowas.
I've also had and seen issues with the soles and midsoles. For heavy duty use I want a quality PU midsole and a good toe cap. I have not been impressed with any boot that used an EVA midsole. This year I had the toe cap on a pair of Kenetrek (Mt Extremes) get slashed in the rocks and it started the sole pealing away. My partner last year actually had his EVA midsole (same model boot) start to slip and offset from the boot after a few miles of sidehilling.
Personally, I would lean toward the Scarpas for sheep hunts, but have no issues with the Alaskan's if they fit better.
Yk
