Tried twice this doughnut outlets which also features in Sunday Times where long queues are norm. They got a range of doughnuts and quite alright for me and nothing to shout about. One cost $1 for the original flavour & $1.20 for those flavoured/specialty ones. If buy more cheaper.
Do give it a try but not when the queue is long.
Their outlets:
a) 1 HarbourFront Walk, VivoCity, #02-125, S098585
Hotline: 6376-8238
b) Basement of Raffles City at the Market Place area http://www.vinco.com.sg/ (the website seem to be underconstruction)