A computer reseller claims that Apple’s Retina Display-equipped MacBook Pro is the quickest to complete its upgrade to Mac OS X Mountain Lion on the back of its solid-state drive and its quad-core processor. Apple launched Mountain Lion earlier this week, offering the update for $19.99 on the Mac App Store.

According to New York Apple retailer Tekserve, the Retina MacBook Pro took just 13 minutes, edging out the 2012 models of the MacBook Air, which posted a 17 minute upgrade time. The difference could be chalked up to the two extra cores in the 15-inch laptop’s quad-core Ivy Bridge processors compared to the MacBook Airs’ dual-core CPUs.

In contrast, Macs that are still equipped with mechanical hard drives took three to four times longer to complete their Mountain Lion upgrades. The worst of the bunch was the 15-inch MacBook Pro that uses the traditional unibody design, posting a 57 minute time. Its 13-inch brother barely made an improvement, taking 55 minutes to complete the update.

The 40 minute and 43 minute times for the 21.5-inch iMac and 27-inch iMac, respectively, is more respectable. It’s also somewhat surprising, since these models hail from late 2011 and are still running Intel’s Sandy Bridge CPUs.

Given that an operating system update is a storage-intensive job, it should come as no surprise that SSDs absolutely crush their mechanical brethren. While the 7200-rpm hard drives on the iMacs mark a palpable improvement from the 5400-rpm laptop drives, they still clearly aren’t fast enough to keep up with solid-state storage.