If you're looking for the ultimate multi-sports tracking watch, packing GPS connectivity and smartwatch notifications, you're spoiled for choice.
Well, we've put both through their paces, and have everything you need to know.
Fitbit Surge v Garmin Vivoactive: Design and display
The Apple Watch and Android Wear brigade won't exactly be shaking in their boots regarding the aesthetics of the Garmin and Fitbit smartwatches. They're definitely not pushing the envelope when it comes to design although both watches are well built, lightweight and comfortable.
The Vivoactive comes in just black or white models, with a skinny 8mm thickness. Its full dimensions are 43.8 x 38.5 x 8mm and it weighs just under 40g â and while it's slender, it just doesn't excite visually. It's not something you want to wear aesthetically, and that's a real shame given its immense feature set.
Wareable verdict: Garmin Vivoactive
It comes in three sizes and is made from a flexible, durable elastomer material similar to that used in sports watches. It also boasts a surgical-grade stainless steel buckle.
In terms of waterproofing, it's no contest either. The Garmin's rated at 5ATM, so 50 metres, and the Surge is just water resistant, so totally unsuitable for the pool.
Fitbit Surge v Garmin Vivoactive: Sports tracking
The Fitbit Surge is a multi-sport watch, which means that its features extend way beyond the step and sleep tracking of the Fitbit Flex.
The Surge represents a wearable for proper fitness types, so running, cross-training, biking, strength and cardio workouts are all tracked. It's also recently added an excellent cycling mode, and Surge users get far more advanced workout summaries than Fitbit Charge HR users.
It will also measure all the basic Fitbit metrics, too.
By sticking GPS on the spec sheet â making it the only Fitbit to accurately track distance â it means essential stats like pace, elevation, split times, route history and workout summaries will be accurate.
However, the Surge's biggest trick is the continuous heart rate monitoring. As it tracks all the traditional statistics, the Surge keeps tabs on your ticker, which means it can colour activity records with accurate information on how hard you were working â which makes it way more detailed than most other fitness trackers.
While the Fitbit Surge is great for running and cycling, the Garmin proudly one-ups it.
There's support for the usual running, walking and cycling, but also for golf and swimming too, making it somewhat of an all action hero. The benefit here is Garmin's superb heritage in making dedicated sport watches, such as the Garmin Approach golf watch and Garmin Swim. Loads of the features have dripped down too, so the golf app, for instance, has information for over 30,000 courses.
There's no continuous heart rate monitoring on the Garmin, though you can hook it up to a chest strap if you want to track your workouts, and that is a downside.
Another important point to note was accuracy. In our tests we found the Fitbit Surge to lack the same GPS accuracy of the Garmin, meaning that often our runs appeared shorter â which is a very important factor.
Finally: the issue of battery life. The Garmin will last three weeks, although our testing averaged at about a week, without too much use of the GPS. The Surge needs charging every five days, so just slightly worse off.
Fitbit Surge v Garmin Vivoactive: Apps
The Fitbit app lets you see your workout history, daily activity, sleep, record sessions, map routes, and even compete with friends. All that information is logged automatically, but you can also manually log your food intake and earn badges based on your activity. Everyone loves earning a badge.
The good news is that the app is still one of the only fitness offerings for Windows Phone â and of course there's support for iOS and Android to boot.
On Garmin's side, the the Garmin Connect platform is one of the best for true fitness types, providing some of the most in-depth overviews of training sessions, and a great choice for data lovers.
Unlike some devices, the Vivoactive works with the mobile app and desktop platform, and is one of the quickest devices to sync we've seen.
Vivoactive works with Connect IQ. It's a new Garmin platform which opens up APIs to developers to make new apps. That means the Vivoactive will evolve over time, and the list of tracked sports could grow to be even more diverse. The Fenix 3, for example, now tracks open water swimming, thanks to canny developers.
Fitbit Surge v Garmin Vivoactive: Notifications
As well as tracking your gym sessions, the Fitbit Surge will display smartwatch information such as incoming calls and texts, and it also has the ability to control your music. There's no third party app support for the Fitbit Surge â so no there's Facebook and Twitter updates to interrupt your workouts, whether you like that or not.
On the Garmin front the Vivoactive also has smartwatch skills, with notifications for incoming calls, emails, calendar reminders and texts popping up on the display.
The Vivoactive is totally inclusive of notifications, and any message that pops up on your smartphone â from vital Whatapps, Uber car arrivals and annoying adverts, will be pushed to the watch. It's impressive, bit could do with improved ways of pruning some of the less relevant ones. However, if you use Facebook, Twitter and Whatsapp â which let's face it is everyone â this is the fitness watch for you.
Fitbit Surge v Garmin Vivoactive: Price
The Fitbit Surge will cost you Â£200, putting it directly head-to-head with the Vivoactive, which retails for an identical price.
Fitbit Surge v Garmin Vivoactive: Verdict
With its vastly superior notifications and bulletproof GPS and syncing, the Garmin Vivoactive is the top choice for fitness fans looking for more from their running watch.
The Fitbit Surge's top mix of heart rate tech and GPS capabilities make it a compelling purchase. However, while it's got the smarts, the app and analytics still aren't becoming of serious fitness fans, and there are accuracy issues with the GPS.
The Garmin Vivoactive might not have the built-in heart rate tracking smarts of the Fitbit, but with Garmin's technology behind it, still excels in every sport. It's certainly a jack-of-all-trades and master of none when compared to dedicated Garmin watches, but if that represents your approach to your active lifestyle, it's a blend of tech that won't disappoint.