Honestly, so far I can't say I have that 'one'... having had probably approaching a hundred or so Busse/kin come through my possession over the years. I think the closest thing so far has been the Choilless Basic 10 LE, but you don't see those much anymore sadly. The Basic 8 LE is close but the choil really barfs me out despite what would otherwise be an excellent field knife. The Boss Jack's are great too, but I really want a choilless one with Res-C handle. Scrapper 5 is pretty close also, along with the Mud Mutt which was very similar, 511 too.
That being said, I've kinda given up on 'The One' for these reasons... in fact my only Busse or Kin I currently own will be the HOG Muk LE I have coming on a trade, which I have high hopes for overall despite the fact that I am fully expecting there to be something about it upon receipt that just bugs the crap of me. A lot to like though, great cutting geometry, actually useful amount of belly for skinning/rocking cuts, compact yet substantial, tip centered in blade, no choil... I'm afraid... truly afraid... because I really can't find anything that bothers me about it right now. Only time will tell I guess... I know... I'm a tough customer... sorry Bossman.