It is better to resize the raid0, because u have to make changes the raid configuration. To resize RAID partitions, there is free space on other data partitions, you can simply shrink other virtual partitions and then extend the system partition. OR u have to add another disk to the RAID array, u need to move the Unallocated space to the end of the system partition. The operations are the same with resizing physical disk partition.
For more info, please have a look here…. though this link is telling about raid5, but it may help to clear ur concept !
Hope it may help u