I have both and I like them both very much. I like the color and glossier, satin finish on the Kiwaya a little better, but I like the diamonds and squares on the Martin fingerboard, (having the Martin name on the head doesn't hurt either). My KMS-K has a 1 piece top and back, so that's a wash for me, (I believe that most KMS-Ks have a 2 piece top and back). They both project well, play great all the way up the neck and both have a classic look. The Martin has a thicker and nicer Ebony fingerboard, so your fingers don't tend to get as close to the top as when you play the Kiwaya. The Martin is a little heavier, but that is probably due more to the thicker Ebony fingerboard and thicker head than anything else, (I use a Uke Leash, so the added weight is not a negative for me. Ebony is very dense and heavy). Martin doesn't make a 3K any more, so unless you find new old stock, you'll be buying used. If new, the Kiwaya will probably cost more than a used Martin 3K. Neither come up for sale very often, so it seems that their owners are satisfied. I know that I love both of mine, but in my opinion, my Laughlin 3K is better and more true to the vintage Martins then either the Kiwaya or the Martin, but even harder to come by. I don't think that you could go wrong with either if they are in very good or better condition.