The High Roller was a very fun experience. I went with my family for my mom's birthday. We got our tickets around 12am. Purchasing our tickets went smoothly. They also provided great customer service.
Once we got to the line, we had to rush a bit for our ride. Luckily, it wasn't busy. We were able to use a whole cabin to ourselves. But if you are unable to move quickly, I would speak to them and ask for information about their procedures before buying a ticket. They don't stop the wheel for you to get on.
The whole ride was one spin but took 30 minutes long. There was even a small count down till we reached to the highest peak of the ride. Had a fun time.