I found the doors not to be too much of a hindrance in mine (even after now owning a D1 and D3). There are plenty of ways of fitting fridges (behind front seats, pull out slide on top of drawers, etc) plus making sure everything else is easy enough to get to. If you want to go the extra mile for access, you can replace the rear sliding windows with gullwing lift up doors.
The great thing about Defenders is they are a mechano set and easily modified with every type of accessory known to man (and woman) available for them via OEM or aftermarket sellers. I travelled all over Australia with my partner at the time, and never had a problem with space, even when lugging caving and climbing gear. The more space you have, the more you tend to fill it though, and the heavier you get. Ask any 130 owner!
Life is just a series of obstacles preventing you from taking a nap.
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