S18
The S18 standard version is $1999. It's $2299 for a 'Special Edition' with improved batteries. Although slightly smaller capacity at 903Wh, they provide more power--not range, but torque. The S18 has an innovative design with an adjustable air suspension system, which requires an included hand pump to adjust two settings. The retractable trolley handle has anti-spin as an option. Six hours for a full charge with its included single 2.5 amp charger. Two 5 Watt high beam and two 4 Watt low beam headlamps, with a sensor to automatically switch between high and low beams. Tail light display for braking, automatic turn signals, and battery level. Low battery throttling to begin at 30%. Quick Charge 3.0 USB power port for your portable devices. Tilt back if the motherboard temperature reaches 176° F or the motor reaches 248° F. Unlike most previous King Song models, the S18 does not have Bluetooth speakers for music or side LEDs. Two color choices, black or white and both have a glossy finish. (The black is not rubberized, as the picture appears or like the 18XL).

16X
The King Song 16X sells for $2089 and has a rubberized matte black exterior, with leg padding. It has four 5 Watt speakers, plus a 20 Watt sub-woofer. Retractable trolley handle, which has built-in anti-spin features. Its 9.5 inch long pedals close magnetically and are 7 inches off of the ground. The 16X comes equipped with a rear mud guard with a reflector on it. There are two charge ports, for quicker charging with an optional 2nd charger, and two USB sources. One of the two USB sources is USB QC 3.0 power (2A) and the other supports plug and play music (500mA). Bluetooth is also included for wireless connectivity for both the App (Android & iOS) and audio play. Along with programmable LED light rings, it has a 5 watt headlight that's 800 lumens, brake lights, and separately also turn signals. An optional padded seat is available for $75. The 16X itself is 7 inches wide.

16XS
The 16XS is $1550, with a battery half the capacity as the 16X, bringing the top speed down to 28 MPH and the weight down by a few pounds. The range is cut in half to about 30 miles.

18XL
The 18XL is $2050. From both eWheels and EUCO, it should come with the larger 10 inch pedals installed.

I recommend the black, rubberized coating, because it is more than just a difference in appearance. The rubberized coating provides a better, more comfortable grip, with whatever part of you is in contact with the exterior. That extra layer is more resistant to damage and can remain better looking, since lighter coloring may show scuffs more. I think the coating might quiet the ride by a tiny margin.

The 18XL has Bluetooth connectivity with your smartphone to view the King Song app and to play audio through the built-in speakers. The built-in EUC speakers play audible warnings, choose between verbal warnings or sound effects, including a horn in the app, and can play music from your smartphone, loud enough to enjoy while riding. There is a headlight and a red tail light. The tail light acts as a brake light. Depending on the direction of travel, the head and tail lights will switch places automatically, so the headlamp is always pointing in the direction of travel. The lights can remain on or off, be triggered by darkness, and can be steady or flash rapidly.

The 18XL has two USB power ports for your devices and two charge ports to cut charging time in half, if you have a second charger.

The retractable handle of the 18XL is easily the best trolley handle system of any EUC made. It is possible to seamlessly go from riding to walking by unlocking and pulling up on the handle as you dismount and continue walking without even breaking your momentum, and importantly with the handle at the right height and angle. No wheel has come up with something so smooth and easy to deploy, and to use as comfortably. King Song pioneered this convenience. While it may not seem important to you now, I assure you, when you're walking around with your wheel, it will quickly become apparent how great it is to have such a design. The trolley handle is so well placed, with its diagonal positioning, that even with no power at all it is possible to comfortably walk with the wheel.

The 18XL has built-in anti-spin features. When the handle senses nearly the full weight of the wheel pulling upward, wheel rotation is prevented. Two beeps signal it sensing enough pressure to stop, then one beep signals when the wheel is engaged again. It also allows for the 18XL to be put on its side while still on, but without spinning out of control. The lift anti-spin feature can easily be shut off from the app. A momentary push of the power button does not turn on or shut off the 18XL. Instead, a one second press is required to turn it on or shut it down. The 18XL will not begin throttling down the top speed until the battery drops below about 25%.

16S
The 16S is $1299 to $1350. From eWheels comes with the larger 10 inch pedals installed. And from EUCO comes with smaller stock pedals. It comes with a built-in trolley handle, now with an anti-spin lift sensor. Like the 18XL, the trolley handle makes it a breeze to take the 16S anywhere--very little carrying needed, because it moves around like a compact, powered suitcase.

The 16S has Bluetooth connectivity with your smartphone to view the King Song app and to play audio through the built-in speakers, with a separate button to power up just the Bluetooth speakers, not the motor. The built-in EUC speakers play audible warnings, choose between verbal warnings or sound effects, and can play music from your smartphone, loud enough to enjoy while riding. There is a headlight and a red tail light on the front and back, which instantly switch if you change direction. The lights can remain on or off, be automatically triggered by darkness, and can be steady or flash rapidly.

The 16S is available in white or a rubberized matte black exterior.

14D
The 14D is $899. From eWheels it comes with the larger 10 inch pedals installed. And from EUCO and Amazon it comes with smaller stock pedals. The 14D includes a retractable trolley handle with anti-spin, built-in speakers, head and tail lights, and colored LEDs on the sides. One USB power port is available to charge a device. This is the least expensive and lightest model offered here in the King Song line-up. For 39% more cost, the 14S will double the range of the 14D. It is available in black or white, each is a glossy finish.