He said having the Moanas there gave the group a real sense of purpose.
The riders had ideal weather, with high cloud and side or tail winds most of the way across the island, and each group had a support vehicle. The biggest hill was on Saddle Rd in the foothills of the Ruahine Range.
It was not a race, McIlroy said.
"Everyone looked after each other. When we were feeling good we went to the front and when we were tired we got a 'tow along' at the back."
Most of the trip was on main highways, and other traffic gave the riders plenty of space.
McIlroy's group of five reached Napier around 6pm, after riding for 10 hours and 17 minutes. They each received a Coast to Coast '21 trophy provided by the Moanas.
They stayed the night in Napier, and after a pub meal everyone was in bed by 10pm.
Seeing the group off and following it in online chats was really cool, Nicole Moana said.
She is humbled and overwhelmed by what the community is doing for "little old us".
Cyclists aren't the only ones that want to help. Edmonds Painting is to repaint the Moanas' house, something George had wanted to do for a long time.
Other friends have finished building a shed that he started, using material donated by Bunnings.
"That was a really awesome surprise for him. I took him out the back to take a video [of his reaction] and he cried," Nicole said.
The family is doing well and about to return to a usual routine that includes school and kindergarten. George has yet to consider whether he wants to have any further treatment.
Meanwhile, they have been "going hard with fun things and activities".
They have been to Wellington for Te Papa and the zoo, and George and Nicole skydived together at Taupō. They have also booked three nights' glamping together in Martinborough.
"We are making lots of special memories, taking lots of photos and videos and documenting everything," Nicole said.
"George has tired days but for the most part he has been strong and is doing really well with everything."
Donations are still rolling in, McIlroy said, and can be made to bank account 02-0792-0124246-002.