You might notice that the 510 isn't on ragweed forge, which seems to have every other Mora knife, that's because it's been discontinued (well I'm pretty sure at least). The 511 is still around though which is just the 510 with a guard, if the guards a problem you can just cut it off though, it's only plastic.
I have the 510, clipper and 120 carving knife (the 120 may have a different blade but the handle is the same as their bigger wooden handled knives I think).
I like the 510's blade, it's scandi grind is wider (higher) which I prefer compared to the clippers grind, at least for sharpening. The handle I don't like however. It's hard plastic so although pretty comfortable, when my hands got sweaty or wet, it would get slippery and since there's no guard on the 510 that worried me a little (the 511 has a guard so I guess that wouldn't really be a problem).
The clipper has a smaller bevel which I found more difficult to hold flat on the stone (I sharpen freehand) than the wider bevel on the 510, but I'm not such a great sharpener so don't base your decision on that. The handle was a little uncomfortable with that rubber diamond pattern but I prefered it to the 510's handle because at least it provided good grip. (I also got a green and black clipper so I liked the colours better than the bright orange 510, of course the 510 was easy to see...)
The carving knives handle (same as the bigger wooden handled knives as far as I know) is the one I like the best, the wood provides decent grip but it's still comfortable. The larger bladed wooden handled knives also have full tangs (I think, there's an x-ray picture that shows that but I can't find it).
So basically if I was buying a new Mora knife based on my experience, I'd choose one of the wooden handled ones.
If you want a plastic handled one then the craftline allround knife looks good (like a clipper without the diamond grip pattern), or one of the soft grip or bushcraft models, those handles look pretty comfy! The 2000 seems pretty good and from what I've heard people like it (no personal experience with it though) but I heard that the different grind on the end of the blade was designed for cutting pâté, so I'm not really sure how that feature would really help you...