See, when you make an SSTO, you put a lot of effort into it and when it's done it is very reliable, so why make another? That's my philosophy. I used to make like hundreds but now i have three: Short Range Transport (2 tons) Long range Cruiser (No cargo one man, Ion engines) and all around workhorse (one man room for 10 ton cargo LKo or one ton to Duna Orbit and back) so there really is no need for me to build any new ones...... <drops in two cents>