You can also inherit from MemoryBase, which gives you a redefined operator new/delete that calls down to PANDA_MALLOC(). Note that this is guaranteed to be 16-byte aligned only when compiling with Eigen.
There are volumes of opinions across the internet about the pros and cons of STL and its relative inefficiency. It’s true it’s not the most efficient toolkit, memory-wise or CPU-wise, but it’s a decent tradeoff between performance and developer effort. And at this point we’re well-committed to relying on STL heavily throughout Panda. 
In the very inner loops, we are more likely to rely on hand-rolled structures for optimum performance.
Agreed! I love alloca; it’s practically free. It’s also unfortunately only occasionally useful due to its nature.
David