There is a cheaper version from Zhulian:

CONTIAGO Bio-Ion Therapeutic Mattress Pad

Uniquely constructed with a combination of 14 special layers of premium quality materials with 7 health-enhancing functions that provide not only a firm support but a more restful and luxurious sleep throughout the night!

Made with a combination of 14 layers of premium quality materials including a top layer of Polyester Jacquard fabric that is quilted with Negative Ion-emitting Non-Woven Fabric, Polyurethane Foam and another layer of Non-Woven Fabric for that added touch of luxury.
Features 7 health-enhancing functions such as Anti-Dust Mite protection, Far Infrared Rays, Negative Ions, Bio-magnetic, Jade Mineral Stones and Thermal benefits as well as provide pure comfort and spinal support to improve your general well-being and allow you to snooze peacefully throughout the night.
The 4-in-1 quilted top layer can be unzipped and detached from the other layers for airing out or cleaning and it can also be replaced with a new one once it is worn out.
Improved material and safety features, such as:
Upgraded model of Thermostat with improved safety and user friendly features.
Improved construction of the thermal layers with upgraded insulated material.
New SAE connector for more secured connection.

RM3200++ compare to Amlife. Not sure its effectiveness.

A friend of mine bought one from Amlife and it works for his wife sleep problem. I am thinking to go for Zhulian or Amlife .