@oschulz I have no idea how I missed your reply. Sorry for that!
SpatialVector, I initially wanted to implement it as a
StaticArray, but I remember there were lots of bugs at the time, and I wanted it to behave as a scalar with regards to broadcasting. Additionally, the performance of
SpatialVector is (was?) in my experience much more deterministic than
StaticArrays (I played a bit with Pauli/Dirac matrices a few months ago, implemented using
SMatrix, and I hit some weird performance issues).
So, basically, I chose the simplest and most reliable solution for my needs at the time, but I might reevaluate it now that
StaticArray is hopefully more stable. I would definitely like to have the free math and composability