That is much easier to use ;)
The filenames in Gcode are very much a hack, there is no standard way to specify string parameters in Gcode. A better way to specify strings is with an "extended comment" e.g. (DATA,Some string). At least this will be ignored by standard compliant GCode parsers. Unfortunately software like pronterface already uses the hacky method to read and write files with the M2x commands, so I implemented the same method for compatibility, but it is really not a method I would like to see used in other commands.
It is assumed that Gcode is not case-sensitive, so we may have problems with lower/upper case. For FAT filenames, case does not matter.
Don't forget that we can put Gcode commands into files on the SD card and "play" them from there. So if you have jingles you want to play frequently it could be a place to put them.
I did write a Windows program to edit music and generate GCode, which people might find an even easier way ;) Sometime I will put the files onto github.