This will make the script terminate on any unhandled error.

It's more picky than you think, so a script which was not written to cope with this probably has unchecked commands which might bite you in the back. (It's good for the self-discipline, of course.)

For example, anything like hello && echo success will terminate the script if hello fails. You need to rewrite that as an if ... then, or artificially add || true at the end.