Some good suggestions, so thanks for them.
I'm taking a canon 5d mk3 which has a 32gb sd and 32 gb cf card, which will suffice for still shots so not a problem there i think. I would like to video most of the journey with an old gopro 2 hero, and this will use a lot of space. I also have a little panasonic camcorder for mucking about with, so will be using that as you can see what your recording with it and you can zoom in on things ( can't with my gopro). Also might take my mavic pro drone as well which will also take quite a bit of footage.
So you can see there is quite a lot of data to shift. The trip is 20 days with 17 days travelling in a motorhome, moving on every day, so no chance of spending hours in a internet cafe trying to upload data for hours ( the Mrs would not be happy ).
There is the weight issues, as we have an internal flight booked from the south island back to auckland and the baggage allowance is only 20kg
.
The Nexto looks promising, never heard of it but looks like a excellent option, other than that i could buy shed loads of sd cards, but this could end up costing more than the Nexto.
Don't have a clue about cloud storage things, if i lost pictures/video then i'd be looking at either Death/Divorce, so i daren't cock this up.
Thanks to all for your helpful suggestions, Duncan.