Microsoft began sales of its Surface tablet running Windows 8 Pro, which was apparently a sell-out through many channels – although with Microsoft not stating how many units were available, it is unclear how much of an achievement this was.

With the launch of the first Surface – powered by the Windows RT platform – having been widely reported as lacklustre, the fact that its premium-priced sibling had sold out in short time led to some raised eyebrows.

It was suggested by some observers that supplies to retailers had been limited – although it is not clear if this was due to a deliberate plan to generate publicity and create an illusion of greater than actual demand, or the result of normal supply constraints for the first batch of an unproven device.

At launch, Surface Pro was made available to customers in the US and Canada. Microsoft has promised availability imminently, although shipments to Canada may take “an extra few days”.

The Washington Post noted that reviews of the unit have been “lukewarm”, with some comment that it is not clear where the device sits – using a desktop platform rather than a mobile one, it differs significantly from rivals including Apple’s market-leading iPad.

Several reviews have been positive, however, noting that when compared with the stripped-down Surface with Windows RT, the new version using Windows 8 does open some new use possibilities.

Microsoft’s pricing for the Surface Pro, which comes in at around $1,000, places it at the top of the market.

The company is also expanding availability of its Windows RT-powered Surface this week, with Austria, Belgium, Denmark, Finland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden and Switzerland being added to the roster.