you are right, it is highly subjective. personally I would write something like:

```js
exec([
  'git commit ' + (opts.signCommits ? '-S ' : '') +
  opts.commitFiles.join(' ') +
  ' -m "' + opts.commitMessage.replace('%VERSION%', globalVersion) + '"'
].join(''), function(err, stdout, stderr) {
```

even though others might argue that is ugly because it is on multiple lines.