I only own three big knives.
Skrama seax, which I think is a fantastic tool, I have found it more useful than a small axe. Sadly I usually go through areas where there are a lot of people and a skrama strapped to my ruck would not go down well. In fact I am thinking of selling it as I just cant use it up and around Dartmoor.
MOD Type D - original model not the new ones. Not as good as the skrama but it will at least fit in my haversack or ruck. Might sell that too, who knows?
Billhook which I use for work, beat up old thing but its a work horse..
Personally, I'd love to be able to take out just the skrama and a whittling knife, no need for a saw or hatchet and a smaller fixed blade or folder but as I say I just don't get the chance on public land. Over winter when the faint hearted aren't on the moors I do use it on occasion and that's why I can say how good it is.