I have still yet to build the KT...I'm honestly not that enthused to start building it, so that may be a rainy day build when ever I finish all my other tanks......or I just may sell it to get another Leopard or Panther. I do have the DT trans brace, bearings and idler adjusters I got from ETOarmour. The idler adjusters are probably the most important and seem to be at the top of the recommendations for the KT. <div></div><div>So far, I think the Pershing, Leopard, Sherman, Panzer IV, Tiger I, KV-1 &amp; 2, and Jagdpanther are the only ones that don't really need anything out of the box for performance improvement. The Panther supposedly needs a spacer to stop the wiggle in the barrel, the KT needs or it's recommended to have an improved idler adjuster and trans brace and even more so if you go metal tracks. Everything else can benefit from ball bearings but notmandatory. Some tanks will need areas improved if you take it a different direction such as adding metal tracks....but overall, I think most all can be just as well stock.</div><div></div><div>Gottarememberthere's a difference between recommendations and mandatory upgrades/improvements....not everyone's a stickler for historical precision.</div>