The actual version 5.05.0 offers the following new features: 

Flight conventions:
Fly together with up to 8 pilots over a local network or the internet
 
New acoustics:
The REFLEX sound output has been completely revised. New high quality model and environment sounds are resulting in a much more realistic flight experience.

Enhanced representation of the models in respect of rotor and exhaust visualization.

A new scenery:
"Wasserkuppe" in Germany.

Model specific channel assignment: This function allows you to define a special channel assignment for single models. Through this it is possible to use in-radio programmed mixing functions.
 
Revised helicopter physics and helicopter model parameters.

5 new helicopter models:
TREX 450SE and 450SE-V2 from ALIGN, Swift 16 and Hummingbird V3 from Century,
Hornet X-3D and X-3D PRO from MS Composit, EP CALIBER 400 from KYOSHO.

Online update:
REFLEX now offers an automatical product update over the internet.

New RMK version 2.43