I currently have a Svante Djarv SK102, which works like a dream plus I didnt have to sharpen it yet and its been in use for over 6 to 8 month, this because of the hardness of the steel, the ones from Svante usually come around 61 rockwell , In my oppinion this is a great plus for a crook knife, as they are not the easiest or fun to sharpen.
The frost I had I had to sharpen after about one and a half month, not bad at all, but I prefer my Svante.
Goodluck with making the decision between the many available knives ^^
Yours sincerely Ruud