It is realy more usefull to work with separate ERM-file instead of map events usage.
Firstly, you're able to test some corrected scripts (not all, unfortunaly) by just reloading a map, you don't need to restart the map in these cases.
Secondly, a script editor (ERM_S) is more suitable to work with scripts, because it gives you an opportunity to create your own workspace by highlighting commands, comments, macros and so forth as you wish.


Moreover, you can create a Declaration or Tag points for each script, that provides you an easy document navigation and exploring.


Also, the editor has many options to optimise your work with scripts, such as creating ERT-files from your internal massage commands if you need to and so forth.