Very much so. You can't ask for a better lot to party with, and if they accept you as a friend, they treat you just like a brother. Since I was born without brothers, I learned what brotherhood was from them. The other side of the coin is that though they don't get angered easily, when they get seriously annoyed, it is indeed a serious matter. And a Viking would be very familiar with the Blutrausch that comes over them during hand-to-hand or CQB during an assault or raid.
I assume you've had experience with them. I can envision that big grin is the last some hapless bad guy sees right before he is eviscerated or his melon cleaved like a green coconut.
Yup.
In an armed conflict where I needed an ally, if I had to choose between one Nepalese Gurkha foot soldier armed only with a Kukri knife, or five people picked out of the phone book who each had a gun, I think I would pick the Gurkha.