The day I hear a useable single coil size humbucker I'll be interested but I don't ever see that day coming.
The moment you change the coil shape of a pickup, ie reduce two coils into the space of one,however you do it-side by side, stacked etc, you're compromising.The strings see a different shape underneath them and the single coil size picks up up tone from a more focused area.
You'll never get a single coil to sound like a humbucker and vice versa...............likewise, remove the hum from a single coil(Strat,Tele, P90 etc) and you'll lose the tone.Not only do the frequencies that carry hum get cancelled but also some of the higher frequencies too that contribute to the tone.Hence why all the noiseless single coils sound so flat and lifeless and...........nothing like the real deal.
If tone is the ultimate goal, which it generally is for all of us, don't compromise.You want humbucking tone, fit a humbucker, you want single coil tone, fit a single coil!
