Hey Danokra, parts from dealer is not an issue (usually ready or 1 day delivery for some parts), service is one of the better deals compared to other car makes (though Toyota and Ford are well supported here too). The challenge is aftermarket parts - I had to order the Bilstein shocks from the states..
Regarding UAE, been here for eight years now, working for a multinational telecoms company with HQ in Colorado. I travel down to Saudi once a month to visit customers. Saudi ok if your on a decent expat package (ie $1000 a day plus expenses!), and living within one of the top 4 compounds. I personally wouldn't live there either, Dubai is VERY different of course, pm if you need to know any specifics