The Polar Grit X is said to have a better GPS antenna setup (and the Vantage V2 should have the same), not just new software, over the Vantage V – so when I got to Florence again, I had to put the two to the test.
For this, I wore both of these watches on my right arm (the left wrist had a Suunto 7 on it).
Having them separated as they should be, there should not be any signal interference between the two. Having them on the same arm should also take away the issue of having the watches point in different directions (and get different views of the sky).
Let me just come out and say it upfront: It does look like the Grit X GPS tracking is quite a bit better.
In the following images, the Grit X track is in orange, the Vantage V track is in blue.
Old Town Canyons
Around the Duomo, on Piazza della Signoria, and coming out at the Arno river, things are quite alright. The differences here are mainly because the watches are on my right (thus, the tracks are skewing closer to the Duomo than they should be and I was) and at slightly different positions.
The narrow old town streets south of the Duomo are hell on GPS, and that includes those of Grit X and Vantage V. The VV’s GPS track, in particular, meander around a lot; the Grit X’s recording still couldn’t be perfect here, but looks nicer.
Funnily, both Polar watches did not capture the time I continued on the same road I had been on, close to Piazza della Signoria, before realizing I wanted to take a turn, thus ran back the few steps and turned.
The Vantage V barely ever shows me on that road; the Grit X makes it look as if I just took that turn, without my error.
Along the river, with the clear view of the sky there, tracks from both Polar watches are pretty nice. Same, up Piazzale Michelangelo and continuing on from there.
Over the hills, it’s all – mainly – good as well. Some offsets appear on the Vantage V, especially one towards the end of the track in the above image.
Back in the Urban Jungle
Coming back between taller houses, the Vantage had a pretty erroneous point in the track. The spot where the houses form a tunnel before turning left alongside the river, interestingly, has little effect (except for a slight but noticeable error in the Grit X track).
Running towards and past Palazzo Pitti, the Grit X is, again, much cleaner and truer than that from the Vantage V, which gets considerably more offsets.
(The squiggly track in front of Palazzo Pitti is me “Playing with Wolves” that were then in front of the Palazzo; those are appropriate tracks.)
Coming towards the (square in front of) Santa Maria Novella railway station, the Vantage V shows a bit of an offset in the track again. Entering onto the square, the tracks are a bit curious; the two Polar watches agree here, but I think I was actually on the other side of the road for a bit longer (the way the Suunto 7 showed me there).
Along the southern edge of the square, all looks good until the Vantage V gets a bit more of an offset yet again, then loses it for a bit as I go into and come back out of the underground passage I needed to use, there.
The last few meters, run in the middle of the road there, are fascinatingly perfect again.
In the end, the Vantage V recorded 9.71 km of distance, 85 m of ascent and descent; the Grit X recorded 9.43 km with 90 m of ascent and descent.
All in all, it’s as I already spilled it at the beginning: The Grit X definitely does have improved GPS reception. The Vantage V is perfectly serviceable; no GPS device (and especially, GPS watch) is perfect – but there are many more offsets from the actual track run on the Vantage V than on the Grit X.
Overall distance and ascent/descent still come out so similarly (and so similar to the distance given for the route I had created for this, and to the measurement from the Suunto 7), the differences don’t really matter for the purposes of training and progress.