"They said it was a fantastic cause to get behind and raise awareness for, but also a great opportunity to meet a few new people, see the country and have a bit of fun.
"I guess it's the reward for reaching out to my network of friends and family, and connecting them with Cure Kids which is an awesome charity."
Brown said they met with a young boy named Finn when they arrived in Hamilton on Wednesday night whose story was particularly inspiring.
"[He had] two open heart surgeries before [he was] four months old.
"[It] just makes you sit back and feel grateful for the family you have, and makes you pretty determined to spread the word and help those who really need it."
Cure Kids chief executive Frances Benge is taking part in the challenge, and said they rely on donations to support critical research projects.
The event will see the teams travel more than 1600km, arriving in Queenstown on April 1 while keeping their expenditure under $10.
The teams will take part in challenges along the way, including cowpat throwing and strength and memory tests.
Brown and Sullivan have raised more than $12,000, and are determined to up the ante before the journey finishes on Saturday.
The decision to dress in cricket whites - complete with vests and zinc - was to appeal to sports fans who might be persuaded to give them a lift.
"We thought New Zealanders would be keen as to pick up cricketers after a bumper summer of the great game. Plus I'm colour blind so it's the only colour in my palette that I was comfortable I looked glamorous in."
Maintaining enthusiasm levels when waiting for a ride was the biggest challenge to overcome for the lads in white.
"We've been fortunate enough to get three great New Zealanders to pick us up so far, but everyone tells stories of waiting for hours on end to get a ride, fingers crossed it won't be us but there is always the risk.
"Highlights of the trip so far have been meeting Finn, jetskiing on Lake Taupo, being shouted two pies, a coffee and an egg sandwich, and getting to know a few bloody good Kiwis."