I realize this is an OLD thread, but since it's been resurrected I thought I should point something out.
While I am a big Mora fan, they do not have sheaths that are adequate for being carried upside down, IMO. Unless you make(have made) a sheath with better retention. Some are better than others, but all of the ones I have, will fall out with a good jarring.
Also, someone commented about the tang length of Mora's. Some models are close to full length, while other do have very short tangs. personally I like to stick with the original and the #510: