ASUS' second-generation smartwatch isn't the design revolution some will have been hoping for, but it's still the best-looking rectangular Android Wear device we've seen.

ASUS didn't talk about its second Android Wear device, the ZenWatch 2, on-stage at its pre-Computex press conference today, but we were able to spend some quality time with the watch in Taipei today. In essence, it's a refinement of the design of the company's first Android smartwatch — not a drastic departure from the previous generation, but good enough to stand out in a sea of circular Android timepieces.

It's easy to see where ASUS is coming from with the ZenWatch 2's design. It's clearly based on the rounded rectangular design of the original, and it looks and feels like it belongs to that same device family. It's difficult to quantify exactly how "premium" it feels compared to the competition in such a short space of time, but it's still relatively thin and lightweight, though with somewhat hefty bezels compared to some rivals.

ASUS becomes the first Android Wear manufacturer to offer a choice of sizes.

We're talking about the ZenWatch 2 as a singular device, but there are actually two versions — one full-sized ZenWatch 2 taking 22mm watch straps, and a smaller version using 18mm straps. The size, shape and feature set are the same, but the smaller version could open up Android Wear to a wider audience given the relative heft of most Android watches. ASUS reps today suggested women might be more likely to opt for the smaller size — perhaps an acknowledgement that female buyers are under-served by most smartwatch manufacturers besides Apple.

The other side big hardware change is the physical button on the side. It's not a digital crown like on the Apple Watch, and you can't turn it. Instead, ASUS tells us, you can use it wake and power off the device, just like the many button-using Android watches currently on the market. It's a minor point of convenience, but not a huge deal.

Zenwatch 2

Elsewhere, the ZenWatch 2 is all about customization.

Elsewhere, the ZenWatch 2 is all about customization. ASUS says there are some 18 combinations of strap and body color to choose from, including three stainless steel color options for the steel chassis — gunmetal, silver and gold. At today's ASUS event we also spotted a host of strap combinations in leather, rubber and metals, including an Apple Watch-like milanese loop. Between this and the two size options, ASUS looks to be offering considerably more choice than even Motorola, with its Moto Maker-enabled Moto 360.

The manufacturer has also overhauled the way the ZenWatch 2 charges. Instead of the bulky, clunky rubber charging dock of old, the ZenWatch 2 uses a more lightweight magnetic charging cable to do its thing. And ASUS is also offering a backup battery for the ZenWatch 2, which fits onto the rear of the device and can be used to charge it while in use — at the cost of making it considerably thicker, of course. This backup battery also has its own magnetic charging port, so you can charge it individually, or charge both the watch and the backup unit at the same time.

The units on display at ASUS' press conference were looping through the usual Android Wear demo reel, but the company says it'll launch with its own suite of software tricks on top of the latest version of Android Wear. This includes a "wellness" application for health tracking, along with camera remote controls for ZenWatch 2 owners who also own an ASUS phone. And ASUS is even working on an app to let users build their own watch faces. None of that was on show today, however.

ASUS reps tell us that the ZenWatch 2 will be launching in the third quarter, with September being mentioned as a likely release window. So it's still early days for the ZenWatch 2, and we'll probably see more of this latest Android smartwatch in the run up to the IFA tradeshow in Berlin.

In the meantime the watch has made a positive first impression. It's not the design revolution some are hoping for, but it's probably the best rectangular Android watch we've seen so far.