Remass

Frankly, it's because I had no idea what the current version was and either thought it was still 1.4.1 or was trying to generally refer to the 1.4 series and didn't want to truncate the version number, I can't quite remember.

I have yet to move on from 1.3.1 too, mainly because 1.3.1 has proven remarkably stable despite the number of mods (some of which are actually made for even older versions of the game) I have in use, and because many of the mods I use have yet to be updated for 1.4.1. I am considering transitioning to 1.4.1 once the mods I use are all updated for it, as personal kerbal parachutes is a big draw, but it's not pressing for me.

In my opinion, unless you're going to recover the launcher vehicle, rockets are pretty universally superior for cost and capacity compared to vertical launch SSTOs or spaceplanes, as you don't have to drag as much tankage along with you. On the other hand, if you are willing to and can reuse your rockets, it's generally cheaper to do so. Without mods to assist in dropped stage recovery, the only way to safely recover much of your rocket is to use an SSTO, making them more cost-efficient than unrecovered rockets.

I spent the day creating a set of four generic, relatively small launch vehicles for various specifications of 6.4 scale kerbin LKO (which takes ~7km/s to meet), to simplify construction when building light probes and the like.