Forgive me for appearing confused Hamish, but is there more than a semantic difference between "daily roaming" and "pre pay Roaming"? If so, I would appreciate someone explaining that to me in layman's terms
First thing I would point out is if you are away for 9 weeks then any charges would be spread over two or even three months of accounts. Secondly if on the $5 a day plan and not going over your plan limits then it should be your only cost and is based on 24 hour periods so not every day is charged if you have your phone off. I see charging has been discussed so I leave that aspect to those who know better.
All I can say is that being able to call family and carry on business as normal for me is the difference between only being able to be away for a couple of weeks and being able to take 6 or 8 week breaks, a couple of times a year.It is a freedom to communicate and for my location to be irrelevant - apart from time zones <g>.
In China I do use a local sim card sometimes as the NZ cost is high, but in reality it is inconvenient as it is not a number everyone knows so nowadays I keep my NZ phone on everywhere I go too. Finally for Europe and the US $150 per month (30 x $5) was the equivalent to a single phone call in my first days of travel and now I just budget it in as a travel cost. One less ice cream or soft drink a day!
Hope you don't mind me putting down my logic on roaming and regardless of which way you decide - have a great trip!
Many thanks to Coffeebaron and Crosis for their contributions to this exchange. I guess when comparing the daily roaming cost to the cost of flights etc, it may well seem minor, but when it has taken around 5 years to save for this holiday, costs remain very relevant. Also it is difficult not to make comparisons with the many free or no cost options for maintaining communication with friends and family whilst away - Skype and Messenger being only two of many. I accept these are dependent upon access to wi-fi but even cash-strapped Greece and Brexit Barmy England each have plenty of that.
No doubt Vodafone could develop something similar, but why would it when it has so many cash cows to milk?