About speed,
IMO, it's just funny to compare LISP routines and most of the time the differences are minor. It become important if the routines are used in many iterations or recursive callings.
For example, the speed differences between command and entmake (entmod) or vla* functions realy doesn't mater while there're used with a user input.
More, if speed is the goal, we'd rather forget LISP and use other languages. We had a challenge
here with "multi languages replys" and we can see .NET is about 2 times faster than LISP and C++ (ARX) about 10 times...
