Witch is better

Well it depends. Ksp is a much more finished game with career mode more planets the ability to plant flags etc while also being easier to mod. SR2 on the other hand is less finished but is more customizable has better graphics and vizzy. It really depends on what you want. I have played both games but I do play Ksp more.

@SNSA why can't it be both?

I wouldnt just easily choose one here, they're both great in their own ways and KSP is quite a bit more matured in terms of content and structure.

SR2. period. its actually much better because you might not have those modules like in KSP, but we can do something even better, make our own ;), we can do much more here than in KSP (i havent played KSP in forever anyway...)