The Roc, the Terra and the Cross Plus overlap enough to make the choice hard and differ enough for it to matter. The short version: the Roc is the lightest, the Terra has the largest map, and the Cross Plus is the one with a published weather rating and ANT+.
The figures side by side
Roc: 2.7-inch screen at 240 x 320 pixels, 120 g, 58 x 90 x 20 mm, 18 hours of battery, 32 GB, dual Bluetooth and Wi-Fi, six buttons.
Terra: 3.7-inch screen at 480 x 640 pixels, 198 g, 80 x 115 x 19 mm, 15 hours of battery, 32 GB, dual Bluetooth and Wi-Fi, seven buttons, USB-C.
Cross Plus: 3.2-inch touchscreen at 480 x 800 pixels, 172 g, 63 x 110 x 21 mm, 20 hours from a 3300 mAh battery, 32 GB or 64 GB plus a card slot, Bluetooth, Wi-Fi and ANT+, IP67 and MIL-STD-810.
All three track GPS, Galileo, Glonass and BeiDou.
Roc: the cycling unit
The Roc is the one TwoNav designed specifically for cyclists, and at 120 g it is the lightest of the three by a clear margin. It turns a track into a roadbook with directions and alerts, offers alternative route variants for when conditions change, and has more than 200 real-time data fields. The German magazine World of MTB named it the best MTB GPS of 2024, pointing to its compact size, its screen and maps, and its navigation features. Choose it if weight and bar space come first.
Terra: the big map
The Terra gives you a 3.7-inch screen with four times the pixel count of the Roc, built to stay readable in direct sunlight. You can create a route point to point on the device, or change one that is not working. World of MTB named it the best MTB GPS of 2023 and highlighted the screen, the map quality, the connectivity and the synchronisation with training apps. It is also sold for hiking and water sports. The cost is 78 g more than the Roc and three hours less battery. Choose it if you explore more than you race, and want to read the map without stopping.
Cross Plus: the all-weather one
The Cross Plus is made for both hiking and cycling. It is the only one of the three with a published IP67 rating and MIL-STD-810 testing, the only one that lists ANT+, and the one with the longest battery at 20 hours. It has a touchscreen as well as buttons and a joystick, and a barometer and digital compass on board. Choose it for bikepacking, for monsoon riding, for rides that end in a walk, or if your sensors are ANT+.
If none of them is enough
For several days away from power, look at the Aventura 2 Plus: 36 hours on a removable 6000 mAh battery, at 290 g. For a motorcycle, quad or 4x4 there is the Aventura 2 Plus Motor, which adds road maps to the topographic map.
Before you order
Two things are worth confirming with us first: which map is supplied for where you ride, and whether your existing sensors will pair. The cycling GPS page has the full comparison table, and how to choose a cycling GPS in India covers the questions behind the figures.
