I love Singapore but I'm not sure it would be the best option for a long weekend getaway ex QLD. It is likely to be uncomfortably hot, has no beach, long flight from Queensland, plus on average it would be amongst the world's most expensive cities for hotels and mostly the hotels are bad value for what you get vs other cities in Asia e.g. BKK, HKG. Unless you want to spend the weekend shopping I would suggest trying elsewhere.
Personally for a long weekend I'd say Fiji would be your best bet. It's a short flight, the weather should be quite good in August, you can sit by the beach in the sun, and I think you'd find it much better value for time, effort and money.
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Also I'm really not sure about the Four Seasons Singapore... maybe I was missing something but I stayed there a few weeks ago and thought it was really average. It is terribly dated and could easily pass for an early nineties era Sheraton. The straw that broke that camel's back was when they offered ridiculously, painfully slow free internet as part of Amex FHR but they try to charge for the 'premium' internet that is actually useable. At a $20/night backpackers hotel I could understand this, but at a Four Seasons it just seemed that they were nickel and diming their way into brand-ruining mediocrity.
I ended up leaving and going to the Ritz Carlton which was marginally more expensive but far, far better. The most spectacular views of the Singapore skyline, perfect location, and the kind of incredible service where they remember your name and favourite drink when you walk into the club lounge. Anyway, IMHO there are MUCH better hotels in Singapore than the Four Seasons - the Ritz Carlton and Intercontinental would be my suggestion. Even the Fullerton is quite good and you can sometimes get some very decent deals there.
First world problems I know...
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