The handy built-in snapper means you'll be able to take pictures on both devices, and have them automatically geotagged so you know exactly whereabouts they were taken for future reference. As for storage, you've got 850MB of internal memory to play with, but a microSD card slot will let you expand this if you get particularly snap happy.
The pair also boast a tilt-compensated 3-axis electronic compass, so it knows which way you're facing even when you're not holding it straight, and are waterproof to help survive our wonderfully unpredictable weather.
A further key addition to the 550 and 550t is its enhanced, sunlight-readable 3-inch touchscreen display so you'll be able to see where you're supposed to be heading even if the sun should decide to make an appearance.
Weighing in at 193g, the duo come with rechargeable batteries to provide up to 16 hours of battery life on a single charge.
So what's the difference between the two? The 550t comes preloaded with 100k topo full European map in 3D elevation perspective – so if you're going off travelling, it may be the better option for you.
As usual with Garmin devices, there are a whole host of additions you can make via microSD or DVD, including City Navigator for driving, or BlueChart g2 maps for sailing types.
We're still waiting on pricing and availability, so while you wait have a nosey at what we thought of Garmin's flagship GPS watch, the Forerunner 405.