hi guys! I recently built a Stinger 40 and a Stinger 10 kit.... in the .40 I have installed a OS .40 SF with Slimline pits muffler and in the Stinger 10 I`m in doubt yet... I have a OS .25 and a Magnum .15... which of them I should install? .25 is too much? .15 is enougth? Both planes haven't flyed yet... I'll take some pictures of them and post here...