Here are Lola's conclusions on the six best-selling systems. Just click below to visit each version.
Each system is reviewed and given awards for areas where it excels - if applicable of course.
Browse the list below to see exactly what usability expert Lola Oyelayo thought of each system tested.
1st BMW iDrive
The most impressive feature is the screen size, says Lola. Its big enough without being overwhelming, and is cleverly divided by the split screen and horizontal menu selection. This allows it to present lots of information without overwhelming you, although it can be a little daunting until you get used to it.
The system also always presents a strong visual link between what you are looking at and what you are trying to do. For example, there are visual clues as to how to turn the dial or use the joystick feature to go backwards and forwards through the menus.
Having the option of storing your favourite presets is also a winner. Storing a function is easier than inputting a new contact to your mobile phone, so every owner should be able to take advantage of this.
Whats more, BMW has also headed off one potential downside of the eight preset buttons: thats a lot of buttons for most people to remember what theyve programmed them for, but the car maker has added a neat touch that allows you to hover your finger over each button so it will display what you have saved there. Thats incredibly useful.
Big screen, simple buttons and rotary controller make iDrive easy to use
Most pleasurable experience, Best input mechanism
2nd Audi MMI
'Audi's MMI system is consistent and logical. An example of this is the way colour is used to provide a cohesive experience as you scroll between functions for instance, telephone options are displayed in green and navigation options in yellow.
'The buttons surrounding the central dial provide a simple way of accessing the main functions, although the four 'free' buttons that change functionality according to which feature you are using add an unnecessary level of complexity.
'The control dial should have been simple to use, but actually took some learning as it operated in the opposite way to what I expected: turning it anti-clockwise moved the selection up, not down. This may be because it was designed for left-hand-drive cars. 'Top marks go to the voice control. Initially, I just guessed what commands I should be using, with some success and some failure. To get any commands right is a good indication that the system is intuitive. Once I had learned its language, it was also able to understand complex requests 'call Lola's mobile' worked, whereas in other cars you would have to first say 'telephone', then 'Lola', then 'mobile'.'
Helpful use of colour; counter-intuitve dial; excellent voice control
Awards: Best look and feel; best voice control; =best steering wheel controls