JS/CSS Compressor configuration is finished, Now site text styles and looks is good. But Site load time

if I Install the JS/CSS Compressor plugin my site load time is 5.21Sec.
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If Uninstall the S/CSS Compressor plugin site load time is 3.80Sec.
Slide2.jpg

May I know any benefit in the JS/CSS Compressor plugin?

Any idea (or) advice for this.

Ram