The ceramic stone from my Smith's 3 in 1 fits perfectly. No point in buying something new when I already have something which works fine. It will also do serrations because of the tear drop profile. Until I find some super cool ultra solution to replace it, I'll go with that for a while...I don't field sharpen often enough to warrant spending anything.

SwampDonkey: The LMFII is a horrible bushCRAFT knife. It's beefy, heavy and has a very thick blade...most of the straight edge is covered with serrations...it's designed for helicopter egress after all. Because of that I haven't been using it as my main carry knife when I'm out in the bush and therefore I haven't been using it very much at all and really haven't put it through any serious bush. I've just started to use it as a light weight solution to leaving my shovel, machete, axes, etc at home. It's lighter than any of those tools and can do all their jobs even if less efficiently...and I would trust it to stand up to way more 'non-standard' use than any of my other bush equipment. It's short for a big heavy knife so it's easy to lash to a pack (the sheath makes this easy...lots of holes and slots).

I look at it as more of a multi-use tool than a bush knife at the moment.