Thanks everyone for taking the time to reply!!I now have an understanding behind the two modes
![Thumb](images/smilies/thumbs.gif)
Thinking back to the IR training,when in the descent from a flight level to another level,i`d reduce power pitch down to maintain speed and accept the ROD = sounds like "level change"
And then from the hold outbound towards the base turn i would nominate a vertical speed ="Vertical speed" mode.
Thanks again.