I am not a fan of Koetsu myself, but the arm will be ok with it. You might check with VPI as to the rear weight you will need. I am using a Benz LPS which is very heavy, but works very well with the VPI arm. (I have a 10.5i, but the 9 incher is very similar). Personally, I love the Benz cart...but of coarse, your taste should give precedence over mine.
VPI Scoutmater II W/JMW-9S/Lyra Delos
I'm considering purchasing a VPI Scoutmaster II with the JMW 9 Signature tonearm, coupled with a Lyra Delos cart. I have read reviews saying the Kleos is better, but some say the Delos is as good or even better. Is there a better matching cart in the same price range? I am asking for suggestions or comments. Also, does the JMW 9S have the mass to support a Koetsu Usishi Black?