These E-Series Alto saxophones are in production and should be available in April 2019:
Rheuben talks about the ES-Series Alto & Tenors
Brand Name: Kenny G
Product: Kenny G E-Series E-Flat Alto Saxophone
Model No.: KGASLS-ES
Finish: Silver Plated Body, Neck and Bell Section, Lacquered Main Body and Keys
Engraving: Full Body and Key
Case: Shaped Cordura
Available exclusively on kg.com: $1,295.00
The E-Series Kenny G saxophones are available exclusively on kennygsaxophones.com. These saxophones feature 2 necks, silver plated body, neck and bell section. The main difference between the ES saxophones and the GIV saxophones are single post construction.
*Single Post Construction: Each post that holds the keys on the saxophone are soldered directly to the body of the saxophone. Single post construction provides a very quick response throughout the entire range of the saxophone.
*Ribbed Construction: Simple means the post are soldered to a plat and then the plate is soldered to the body of the saxophone.
I my opinion they both have very good qualities and it should be up to the player to decide which is better for them.