There is a BIG difference between a Single-coil and Twin coil side-winders and humbuckers. 

The purist Kinman P-90 Hx is the only true Zero-Hum single-coil.

Stacks:
Stacks have 2 coils, both sense noise and string signal almost equally. The pickup produces almost equal string signal in each coil, and equal hum level in each coil. The coils are wired out of phase to cancel signals in common. Hum is a signal in common and so is the string signal. Both hum and signal get cancelled, but the signal gets cancelled a little bit less because the string is positioned on one end of the magnet so there is a little less signal sensed in the lower coil. The sonic output of the pickup is the difference between the level of string signal between the two coils.

Since the difference is small, manufacturers attempt to magnify the level of that difference by winding the coil with finer wire and many more turns. This increases Parasitic Coil Capacitance within the coil. Excessive capacitance is the arch enemy of good sound. Resistance of stacks is double and three times that of noisy single coils. This indicates a lot of turns of very fine wire.

Sidewinders:
AKA Middle Point Humbucker.  Te Sidewinder design is flawed, it is extremely in-efficient and an inordinate number or coil turns is required to attain acceptable output level.  As with Stacks, coils with very fine wire and lot of turns are necessary to magnify the string signal to an acceptable level. The big trouble with doing that is the massive amount of Parasitic Coil Capacitance in all of those coil turns which impact on transparency and dynamic response and that's the reason Stacks and Sidewinders have a dry sound as distinct to a lush, juicy sound of a genuine single coil such as the Kinman P-90 Hx.

Mojo Tone's Quiet Coil is a Sidewinder wound with 42g wire and weak Alnico magnets, it produces very weak output level.  Fralin noiseless P-90 is also a Sidewinder and both have about 14 parts. Fralins coils are crammed with excessive turns of fine, high resistance wire, the result is excessive coil capacitance which destroys dynamics and the lush feel of a genuine single-coil P-90.

Kinman's P-90 Hx: is a true single coil and our Gen-3 v2 hum sensor with it’s very low Parasitic Coil Capacitance means there are no compromises in sound quality.  It does not interfere with or produce string signal so our high-output, absolute Zero-Hum Nasty 90 sounds near identical to a conventional lush n juicy non-noiseless Gibson P-90.  Kinman's DC resistance is lower than noisy single coils because our coils are highly efficient and with that comes great benefits.

Kinman's have a dedicated hum sensor, and unlike crude Stacks have a much different dedicated string sensor. There is negligible cross-talk (magnetic coupling) between the two coils thanks to our patented Magnetic Shield and minimized Hum Sensors.  The hum sensing coil, with it's high transparency factor, does only one job, the one it was designed to do, which is to sense hum.  It does not interfere with or produce string signal.

A Kinman P-90 Hx (Hx = Hum Canceling)

Resistance of Sidewinders is about three times that of noisy single coils. This indicates a lot of additional turns of very fine wire. In other words Sidewinders sound awful to anyone who appreciates fine sound character. Sidewinder P-90"s are look-alike pickups, and definitely not sound-alike. They sound nothing like a real P-90 what-so-ever.

Kinman's DC resistance is often lower than noisy single coils.