Usage and Impressions
Convenience. It was clear from the outset that the Stack wasn't directly aimed at everyday consumers. Rather, it's aimed at business-people and the enterprise with a fleet of employees that travel often. The Stack was engineered with that person in mind -- the person who continually works from a mobile office, and perhaps has to setup a presentation and conference call in a new boardroom each week. When your office is perpetually on the move, having these four items quite literally snap together stands to make life a lot easier.
In our testing, that's exactly what we found. The sheer size and weight of the package is impressive. While it's appropriately dense, it can fit into even the smallest saddle bag, taking up minimal room in a frequent flyer's carry-on. As for software, you'll find a ThinkPad Stack Assistant available for Windows, iOS, and Android. Though setup is predictably minimal, these programs do enable you to easily tweak the SSID and password of the router, keep tabs on the charge level of the Power Bank, and monitor network traffic as well as available HDD storage.
To give you an idea of where the Stack excels, consider this example. A business-person shows up for a sales meeting in an unfamiliar conference room. To appropriately pitch, he or she needs to showcase a presentation, play a small video clip, dial a colleague in for a brief chat, and be ready to access any number of related files on a whim should the prospective client ask.
The Stack makes all of this a cinch. So long as the 10,000mAh Power Bank is juiced, you don't even need to plug the unit into the wall. That pack is powerful enough to sustain the router, the HDD, and the Bluetooth speaker + mic. So, you toss that in the center of the meeting room, and you have instant access to 1TB of local files (that 1TB HDD becomes a NAS when it's stacked alongside the wireless router), a simple Bluetooth conferencing systems, and even a couple of spare USB ports for anyone in the room who forgot to charge their phone the evening prior.
The router is super slim, and packs a single Ethernet port on the rear and suppors both 2.4GHz and 5GHz (802.11a/b/g/n/ac) network connections. There's a micro-USB port for keeping it juiced via USB -- no AC adapter required -- or it'll power up if stacked with the 10,000mAh Lenovo Stack battery pack. The associated software even allows it to bridge an older device without a Wi-Fi radio onto a wireless network.
The router is sold attached to the 1TB HDD, most likely to showcase the convenience of network attached storage. Foreign meeting spaces can be tricky when it comes to Wi-Fi. Oftentimes, corporations do not have reliable guest networks, so relying on cloud access to pull down giant presentations isn't wise. The 1TB HDD enables you to keep your critical files local, yet access them wirelessly in the room. You can even transfer files back and forth between a mobile device, or plug directly in for a standard USB 3.0 transfer. As for performance, we found it pretty typical of similar 2.5-inch HDDs. It'd range between 100MB/s and 120MB/s during typical read and writer operations.
The 10,000mAh "Power Bank" is a heavy bugger, but it packs a lot of punch. There are a pair of 5V (2.1A) USB ports for charging tablets and phones, though it doesn't support a fast-charging plug. In other words, full recharges can take a few hours. Our main gripe with this product is the lack of an AC port. While being able to power two smaller devices is fine, this would be entirely more useful if it could also be used to power a ThinkPad (or any other) laptop. Unfortunately, it's a missed opportunity. You'll still need to lug around your laptop's AC adapter, which is a real shame.
Finally, there's the Bluetooth speaker. It supports BT 4.0 pairing and includes a noise-reducing microphone, which allows it to be used as a conferencing device when your Spotify jam session comes to a close. The speaker has a small battery pack of its own, allowing it to be used by its lonesome outside of the Stack for up to 8 hours. If, however, you have it inside of the Stack, it can go for two full days with the help of the aforementioned Power Bank. Sound quality and voice transmission were both above average. Predictably, the bass is lacking, but the audio quality far exceeds anything a modern laptop will be capable of, and it's hard to overstate just how excellent it is to have a speakerphone at the ready for those who routinely work on the road.