Works great!

It took a while to try various combinations of settings to suit my site, but in conjunction with the companion Async JavaScript plugin this got my site from F to A grade (GTMetrix) and 7 to 99 (Google Pagespeed Insights). I also added a couple of other plugins – WP Super Cache and GZip Compression but this one by far made the most difference! I rarely leave reviews but here I am, that’s how good it is.