I'm more interested in a true compiler.
MMG is a true compiler. But that does not mean that its compiled code is much faster than that of ABC. It will just consist of a series of JSR instructions... similar subroutines are also in the ABC runtime, just dispatched by its p-Code, so it does not make much of a difference.
Do not expect an optimizing compiler as you would find them nowadays. They are all - including the TBXL compiler - pretty straightforward.
ABC has actually been more used for "copy protection" purposes as it is quite hard to follow the program logic through the pCode. A couple of Microprose titles have been written with it. Solo Flight and F15 Strike Eagle are to major parts in ABC-compiled BASIC.