Yeah, Northwest lost a bag of mine once. I didn't have anything too valuable in there (the Swiss Army suitcase itself was probably the biggest down-side).

I filled a claim, figured I would have to fight like crazy, but they paid me pretty promptly. I declared the value (the cost, actually) of everything that I remembered was in there, and they paid me what I declared minus "depreciation." It was reasonable -- it's not really practical to replace dress shoes that cost $300 new with some type of used pair for $150, but I suppose it's theoretically possible.