How do you define better?
Obviously you could try both and see what the results are.
Personally I like controlling things inside WP as much as possible so I minify with W3TC or WP Minify and don't use CloudFlare's minification on WordPRess sites. Of course you could run both so that CF picks up anything W3TC misses.
Either way, minification is much less important then concatenation as far as performance goes. Concatenation causes breakage more often than simple minification.