If I could go back in time I'd just spend more on a newer model. I don't like spending heaps on an older car, no matter how much money you put into it it's still an older car with that older car feel and many plastic/rubber hard to reach bits that are just about to f**k out. Hindsight 20/20.
Edit, or maybe at least a 50i X5 (The Twin Turbo V8)
https://www.trademe.co.nz/Browse/CategoryAttributeSearchResults.aspx?search=1&cid=268&sidebar=1&rsqid=bbf3c9aaed3a45ffb13fdb7e585f29dd&sidebarSearch_keypresses=0&sidebarSearch_suggested=0&14=BMW&15=X5&21=&1=&minPrice=&maxPrice=&13=0&13=0&24=0&24=0&309=0&309=0&54=50i&searchRegion=100
But at the end of the day its the same engine, same shitty radiator and PS system with the same issues.