So I have an Epiphone Special II that I got as a starter guitar. I have since bought a mexcian fender strat that I use as my main guitar. I was thinking about putting some EMG's 81 and 85 that I got for $100 into the Epiphone just to have something to mess around with. Is it worth investing the money and putting them in that guitar? If I held out and bought say an Epiphone SG-400 would that make any sense. Assuming they both had EMG's, is the SG going to sound that much better that it's worth upgrading? Thanks in advance for the help.
Do neither.

What's your amp?
R.I.P. My Signature. Lost to us in the great Signature Massacre of 2014.

Quote by Master Foo
“A man who mistakes secrets for knowledge is like a man who, seeking light, hugs a candle so closely that he smothers it and burns his hand.”

What amp?
For a more direct answer, just get a new guitar rather than upgrade the Epi Special. Unless you can upgrade low quality wood, set-up, and some hardware.
will someone carry me across ten thousand miles under the silence
Getting EMGs for a fender blues deluxe is like putting a hemi in a moped.

If anything i'd upgrade the strat.