Hey Ferram, I've been playing with FAR, KIDS, and DREC and it's been loads of fun. Thanks for all of your hard work. I'm learning loads about rocketry. Anyway, I prefer playing stock KSP solar system, so I was wondering if anyone could help further explain the two presets for that in KIDS. First, I don't understand why 'FAR to Stock KSP, Universal' penalizes vacuum ISP. I'm using FAR and KIDS to get more realistic rocketry in an atmosphere, but wouldn't I want my ISP's to basically be stock once I'm in space. Next, I see that 'FAR to Stock KSP, Atmosphere Only' is an answer to my first question, but why does it penalize me so much in an atmosphere? It makes my rocket designs super tall like this http://i.imgur.com/WKAjehd.jpg?1 (I also don't have many parts unlocked. Just a few nodes on the tech tree.) Would a happy medium be more suitable for me? Maybe I should adjust the settings to allow thrust to vary with ISP. I just don't know too much on that subject or how the game handles things like vac/atm rated engines. Thanks!