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Optus E5331 Mini WiFi Modem review: Optus E5331 Mini WiFi Modem

Optus' budget Wi-Fi modem won't give you exceptional speeds or indeed any kind of exceptional experience, but it equally won't burn a hole in your wallet.

Alex Kidman
Alex Kidman is a freelance word writing machine masquerading as a person, a disguise he's managed for over fifteen years now, including a three year stint at ZDNet/CNET Australia. He likes cats, retro gaming and terrible puns.
Alex Kidman
5 min read

Design

Australian telcos don't develop their own hardware, instead re-badging designs from external networking providers such as Sierra Wireless, ZTE and Huawei. The E5331 Mini WiFi Modem is a Huawei model, and it's easy to see where Optus got the Mini prefix from. At 92.8x6013.8mm and 82g, the E5331 Mini WiFi Modem really is quite mini.

8.0

Optus E5331 Mini WiFi Modem

The Good

Inexpensive. Genuinely pocket sized.

The Bad

Very ordinary data speeds. Simple display is a bit too simple.

The Bottom Line

This budget WiFi modem from Optus won't offer exceptional speeds or indeed any kind of exceptional experience, but it equally won't burn a hole in your wallet.

It's also not exactly blessed with a lot of on-screen information, with very simple lights to denote power, battery, SMS, signal and Wi-Fi status. That makes it easy to read at a glance, but the flipside is that compared to the LCD displays on other Wi-Fi hotspots, including Optus' own E589 Mini WiFi Modem, it doesn't really tell you much.

Features

The E5331 Mini WiFi Modem is a very basic Wi-Fi hotspot. It'll support up to eight connected devices at once, and uses a regular SIM card to connect to Optus' HSPA+ network. That's a much larger network than Optus' current 4G deployment, but it's also a much slower network, as it's shared with just about every other Optus mobile broadband and mobile phone device, save for the 4G devices. The E5331 Mini WiFi Modem doesn't have a whole lot of battery space. The supplied unit only comes with a 1500mAh battery, which Optus reckons is good for up to five hours of operation.

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Testing

There are a few key metrics for any mobile broadband network, but testing them is perilous, simply because there are so many variables that can affect one test in one location. So we hit the road and tested seven different mobile devices across six sites to try to get a more complete picture of mobile broadband performance in two capital cities. Why capital cities and not regional zones? Partly, that's a factor of time, but also so that we could get a picture of 4G zones — and right now, Optus is concentrating mostly on capitals for its 4G — as well as the issues that congestion can introduce into a network.

We've tried to mix up our locations as much as possible, with our six sites covering a family home in Hornsby in Sydney's north (outside any 4G zone), Darling Harbour in the Sydney CBD (for an outdoors 4G test, because the 1800Mhz frequency used by 4G LTE has some in-building issues), in Glenelg Library in Adelaide (because it has thick walls and is a busy public space), in a coffee shop in Adelaide's Rundle Mall (because again the walls are an issue, as well as public congestion) and finally in departure lounges at Sydney and Adelaide airports, as they're awash with travellers checking mobile devices prior to boarding their planes.

All testing was performed with the Speedtest.net app running on Google Chrome on a MacBook Air with no other internet-reliant applications running and no extensions installed. Tests were run three times in each location, and then averaged to find ping, download and upload averages for each device.

Sydney CBD results Ping Download Upload
Telstra Mobile Wi-Fi 4G 45.33 13.99 13.97
Telstra Pre-Paid Wi-Fi 4G 16.66 8.8 14.81
Telstra Pre-Paid 3G USB+Wi-Fi 76 7.17 1.18
Optus E3276 Premium 4G Modem 57.66 5.053 0.486
Optus E589 Mini WiFi Modem 56.66 2.48 0.57
Optus E5331 Mini WiFi Modem 120.6 2.26 0.58
Vodafone Pocket Wifi Extreme 122.33 1.5 0.06
Sydney Airport results Ping Download Upload
Optus E3276 Premium 4G Modem 35 41.99 9.55
Optus E589 Mini WiFi Modem 35 13.51 9.91
Telstra Mobile Wi-Fi 4G 46.66 13.35 14.12
Telstra Pre-Paid Wi-Fi 4G 50.33 11.73 11.09
Optus E5331 Mini WiFi Modem 55.66 7.2 0.53
Telstra Pre-Paid 3G USB+Wi-Fi 71.66 6.88 1.19
Vodafone Pocket Wifi Extreme 70.33 2.27 0.2
Hornsby, NSW, results Ping Download Upload
Optus E3276 Premium 4G Modem 57 11.55 1.16
Optus E589 Mini WiFi Modem 80 8.98 1.15
Vodafone Pocket WiFi Extreme 61 8.83 3.49
Telstra Pre-Paid Wi-Fi 4G 48 7.72 1.85
Telstra Mobile Wi-Fi 4G 49.33 7.68 2.31
Telstra Pre-Paid 3G USB+Wi-Fi 59.33 6.65 2.5
Optus E5331 Mini WiFi Modem 73.66 2.75 0.55
Adelaide CBD results Ping Download Upload
Telstra Pre-Paid Wi-Fi 4G 10.33 24.46 6.51
Telstra Mobile Wi-Fi 4G 52.66 14.21 2.5
Telstra Pre-Paid 3G USB+Wi-Fi 72 11.12 1.17
Optus E5331 Mini WiFi Modem 98 7.16 1.11
Optus E589 Mini WiFi Modem 79 1.01 0.12
Optus E3276 Premium 4G Modem 90.33 0.803 0.106
Vodafone Pocket WiFi Extreme 201.33 0.313 0.04
Adelaide Airport results Ping Download Upload
Optus E3276 Premium 4G Modem 85.33 12.47 1.13
Telstra Pre-Paid Wi-Fi 4G 41 10.02 7.42
Optus E589 Mini WiFi Modem 80 8.83 1.14
Telstra Mobile Wi-Fi 4G 33.66 8.34 7.2
Optus E5331 Mini WiFi Modem 89.33 6.25 1.103
Vodafone Pocket WiFi Extreme 95.66 3.33 1.31
Telstra Pre-Paid 3G USB+Wi-Fi 236.33 0.593 0.366
Glenelg, SA, results Ping Download Upload
Optus E589 Mini WiFi Modem 71.66 20.44 1.15
Telstra Pre-Paid Wi-Fi 4G 52 13.55 0.82
Telstra Mobile Wi-Fi 4G 52 13.55 0.82
Vodafone Pocket WiFi Extreme 42.66 11.55 1.35
Telstra Pre-Paid 3G USB + Wi-Fi 76.33 8.49 1.1
Optus E3276 Premium 4G Modem 88 8.17 1.15
Optus E5331 Mini WiFi Modem 85.66 7.03 1.15

Performance

There are a lot of 3G devices out there, and that means when you test any 3G device, you're fighting for scarce resources with every other user out there. As such, we weren't all that surprised with the E5331 Mini WiFi Modem's overall performance, which was always outmatched by 4G devices in the same tests, and sat at or near the bottom of the pack for each test. The exception to this was in the Adelaide CBD, where its 3G status appeared to be a boon compared to Optus' own 4G network, recording a much higher speed. Optus is still rolling out its 4G network in Adelaide, however, so that's a figure we'd expect to see change in due course.

In terms of battery life, the Optus E5331 Mini WiFi Modem lived up to its billing, managing around four hours in our tests, although the lower power drain of 3G HSPA+ undoubtedly played a part in that.

Conclusion

The Optus E5331 Mini WiFi Modem is a cheap and simple Wi-Fi hotspot option. You're not paying a premium for the device or the data, and in return you're getting a very basic service. If you do happen to live in a metropolitan area currently serviced by Optus' 4G network, we'd advise spending a little more on a 4G device, because the speed differences are generally quite remarkable, while the data costs are identical. But if you're after a solid but unremarkable mobile data device, the Optus E5331 Mini WiFi Modem is entirely satisfactory.