I love ColdRock icecream. The one in Helensvale is easy to access and has lots of parking (it's a part of the Westfield Helensvale complex). If you want your icecream well mixed I don't recommend that you go there during busy times. The staff get visibly tired and worn out and start doing a substandard job.
Cold Rock is always good if you like to have some icecream custom made to your own tastes. I do find at Helensvale that they often put so much icecream in, I can't finish it and don't get the benefit of the added flavours - so just ask for less icecream. Watch for vouchers in local publications (2 for 1).