cache static content only bad grade

[domabout]

hello,
Ran speed test and was fortunate to get all A's except for 'cache static content'. Here is results page: http://www.webpagetest.org/result/140108_BA_TRB/

I run opencart. I came across code that might help improve the cache static content grade but I usually don't like loading up .htaccess. Would this be safe to use or any other recommendations:

# compress text, HTML, JavaScript, CSS, and XML
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE application/rss+xml
AddOutputFilterByType DEFLATE application/javascript
AddOutputFilterByType DEFLATE application/x-javascript

# remove browser bugs
BrowserMatch ^Mozilla/4 gzip-only-text/html
BrowserMatch ^Mozilla/4\.0[678] no-gzip
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
Header append Vary User-Agent

thank you