The color of the backlight is one of the differences between the 'consumer' line and the 'total control' (ie. 'professional') series. You can't do anything about the backlight color but it may not be worth it to upgrade to the equivalent remote in the total control series (MX-350) just to change the backlight color.
However, some the other features on the total control series models may be useful for some people in some circumstances. I own the MX-350 and from what I can tell by reading the manual for the RF-20 the differences are these:
1. Backlight color - Red on the RF series and Blue on the MX series.
2. Assignable emitters on the MX series.
3. Ability to select IR, RF, or both for each device on the MX series. The RF series always transmits both IR and RF which is not usually a problem but will be if you have multiple devices that respond to the same remote codes. Assignable emitters solve that problem.
4. I think the RF basestation on the RF series will always send the IR out of both the emitters attached to the back panel and the front 'blaster' panel. RF basestations sold separately for the MX series can do either or both.
5. Color: Black on the RF series; Silver/Gray on the MX series.
Most people won't really need the extra features of the MX series and can save over $200 by going with the RF series.
If anybody needs anywhere near the 192 step limit for macros, their system is WAY too complicated.
