It's called a caching plugin, but it also compresses and minifies stuff. Any site can benefit from loading faster. You can turn it on and let it go. It has sane defaults.
I want you to print this out and stick it somewhere out of sight. When one day you are linked to on Reddit, Slashdot, a major news site or the like, pull it out for a hearty laugh.
Define "sufficient resources". It might be enough for your normal traffic, but without caching those blogs will crash from the /. effect (unexpected traffic spike).
Even with caching, I suspect Apache would fall over if I got slashdotted.
An easy solution like those plugins is such a big win for so little work, I just can't agree with "it's good enough for normal use". The last thing you want is for your blog to fail when you are getting a traffic spike.