Just upgraded my speakers - do I still need the subs

The answer could not be any simpler. Listen to new speakers with subs and without them, you shall hear the diffference.

Can't you turn the subs on and off with the new speakers and decide which sounds better?

Just traded my Martin Requests for Focal Sopra 3, I have two Martin Logan depths sitting in the corner. Not sure I’m going to hook them up.   The Focals in my room produce fantastic articulate lows.

LOL WHAT. Keep the Subs. I don't know why you're even entertaining the thought @fritzenheimer 

If you are staying in the same room and are happy with the KC62 subs, no need to waste money on bigger or "faster" subs. The KC62 and 92 have essentially the same frequency range. The 92's would help pressurize a larger room.