There's the Hwz thread you may have come across. It just happens that just now all 3 sites I went to were not fully functional for a while.
Will be great if Coinbase expands to Singapore
Unfortunately, the direct buy/sell model that Coinbase uses will result in them having to collect GST based on the recently released taxation guidance from IRAS.
Relevant paragraph from
http://www.coindesk.com/singapore-government-how-we-intend-tax-bitcoin/The GST treatment of the supply of bitcoins will depend on whether the company is acting as an agent or principal in the transaction. If the company merely facilitates and is acting as an agent in the bitcoin trade (eg: bitcoin exchange transfers bitcoins directly to a customers wallet), then GST is chargeable only on the commission fees received. However if the company is acting as a principal in the bitcoin trade (eg: it buys and onward-sells bitcoins to the customer), GST is chargeable on the full amount received, ie: the sale of bitcoins and commission fees.