why not simply make a table to hold the data for the value list and create a value list to "Use values from field".
This will allow you to import the values to any other database file instead of copy and paste.
It's not just one value list, it's dozens of them. Of course, your technique would still work for multiple value lists, but my real question wasn't whether to use "get from a field" vs. "get from a custom list", it was "Will I take a performance hit if I get the values from an entirely different FILE, no matter how they're created there?"
Can't say for sure one way or another as I've got no actual measurements to work from however multi-file solutions and the data separation model which use one file to hold the data and one for the UI are common among some Filemaker developers including myself so depending on the solution might not be a big enough impact to make a difference.
The performance hit will depend on how the database location and how they are hosted (Filemaker Pro, same Filemaker Server, different Filemaker Server) as well as how many databases are hosted and how many are utilizing the value list file in a relational environment.
I know, I know getting the "it depends" answer isn't very helpful but that's really all I got in this case since there are too many unknown variables.
The difference in performance for a standard use values from a field value list is negligible. (This may not be the case with a slow hosting connection, a large number of records [100,000+] in the table and the use of a conditional value list.)
Such value lists are also much easier to keep correct when you later release a new version of the file and import the data from these tables along with the data from all other tables.
Thanks, Phil. Since I work almost exclusively with small non-profit organizations where all of the fewer than a dozen database users are literally within sight of each other, I'm going to take this as my go-ahead to start simplifying my value lists to find them a "home" in my "Universal" file (the one that contains only a single record, with basic information about the organization itself) and set everything else to get their value lists from that source.
You might check out the Adventures in FileMaking series. Adventures 1 and 2. They are free to download.
Adventures in FileMaking #1 - Conditional Value Lists (includes details on how to set up a basic field based value list)
Adventures in FileMaking #2 - Enhanced Value Selection (what to do when a simple value list won't cut it.)