The rule of thumb is try before you buy. Read through the script and try to understand what it does. You don't need a script, although some scripts make long tasks much simpler. The best script might be a simple one with a few aliases to limit the amount of typing you need to do. A script can do anything a user can do.
Phoenix is an example of a script that is top heavy, CPU intensive and generally pretty worthless.
There are repeated commands and remaps in the script which merely adds to the overall worthlessness. Of what value is it to map an alias to do different means when one meaning overwrites the other. The coder is a nice guy, but not a great coder. Dreamscript is Phoenix with all the includes and none of the code. It may time out.