MkIII SSTO spaceplanes. Feasible? Profitable?

[Cirocco]

right so I managed a pretty big and heavy SSTO today (140 or so tons) which makes orbit with over 2000 delta-V left in her nukes, and a relatively small bit of oxidizer (700 units for 8 RAPIERs). Should be enough to get me to Duna surface, possibly even back, all on a single tank. Sadly not enough in there to get me to Laythe. This is a purely exploratory vessel, made to go to her destination and back on a single gas tank and without stops or mining. She has a 4 kerbal capacity so far and a small MkIII bay for a rover or other science equipment. Also, no clipping (of which I am quite proud )

I feel like it could still very much be optimised though, will work more on it and report back later. Unfortunately, KSP crashed on me (it seems to do that frequently on ships which have a lot of heat bars showing up) so no pictures. Wouldn't really like posting pictures of an unfinished ship anyway.

[Slam_Jones]

I used this SSTO to build this station in 0.90

Haven't been able to build one successfully in 1.x yet though