It is early to make a judgment about Mach4 that, in our humble opinion, is still being completed since the same manufacturer claims to be in the process of developing many plug-in (even if the parallel port is already available). 

Honestly speaking, we were not excited at first glance to the software. The interface has been certainly cleaned and better organized compared to the 'old' version. It has been uptated and there are many parameters for the configuration of ve arious tools for milling. Very probably the result will definitely be better but habits are hard to forget and honestly we still prefer Mach3, at the moment. It must be said, however, that the company is still working on the software and then it is reasonable to predict future improvements in terms of both plug-in available and wizards.