After almost 10 years my faithful Delorme PN-40 GPS has started to become unreliable. It still works but it thinks it is 1999. It goes through batteries twice as fast as it use to. The connector on back of the unit is so worn it is very hard to get it to connect and sync with the computer. I would gladly buy another Delorme GPS unit but they were recently bought by Garmin so Delorme no longer sells GPS units.
If you want a GPS unit for a bike you pretty much are going to buy one of the models from Garmin. Wahoo does make an alternative but it doesn't match the features of a Garmin. The other alternative is to use your phone but then you need to carry a supplemental battery so the phone will last the entire ride with the screen on.
After some research and some good advice from Jim I bought the Garmin Edge Explore. The Explore is targeted at bikers who want a GPS mainly for navigation and are willing to give up some of the advance fitness and workout measurements like power and V02 max. It got a large 3" screen and more features than I need. Its really a good piece of hardware. The screen is good size and is a little bit bigger than my old Delorme. Surprisingly the Delorme screen is almost as clear as the new Explore even though the Explore has 10 year newer technology.
As with all new toys it takes a while to understand how it works. I did a few short rides with it to get the hang of how to use it. I even did a couple of rides with both the old Delorme and new Explore so I could compare the accuracy between the two. Unlike the Delorme no ride planning software is included. You have to create the route somewhere like RideWithGPS and then download the route to the Explore. Its not hard to do but is not as seamless and integrated as the Delorme.
Once the route is on the Explore and I'm riding it is very similar to the Delorme. On the Delorme I kept the screen on the map view. It had an orange highlight on the route and displayed the next turn as well as distance to the next turn and distance to the end of the ride. On the Explore I can set it up similar to the Delorme but not exactly. On the Explore it is a little easier to switch between screens so I normally leave it on one of the data screens so I can see speed, distance to next turn, time, total distance and heart rate all at once. When I get with in a tenth of a mile of a turn the Explore automatically switches to the map to show you the turn which I like.
After the ride it is easy to connect to my computer and upload the ride to Garmin Connect which I have automatically synced with my RideWithGPS account. I still am getting use to the unit and still need to figure out how to do a few things but overall I'm very happy with it. Today during the Spring Fling I left Chris's ride and headed home on my own. I used the "where to" function to let it calculate a way home. Half the time it would suggest a different way than I wanted to go but then quickly recalculate with out complaining as I ignored its suggestions. Having the Explore show me the approximate distance until I get home was useful as it let me know how direct a route I should take from home.
I know some people that have problems with Garmin GPSs not being able to follow an uploaded route or having other problems with the unit that makes them not trust it but so far I haven't had any real problems. I am the original tech geek. I've worked on the satellites that send the GPS signals to these units so I understand the detailed math and algorithms used by these units to calculate position and speed. If needed I could probably de-compile the firmware and rewrite it. So I think I get a certain amount of respect from these types of devices as it knows I could take a soldering iron and go all medieval on it ass. I also enjoy getting into the details of how the software and hardware works and try not to get angry at these devices. I want to stay on their good side because we all know that machines will some day take over the world.
My only real problem with the new Explore is that the elevation data is low by at least 40%. When I did a ride with both the Delorme and Explore the difference in elevation was almost double. It seems like whatever algorithm it uses to calculate the elevation under estimates the change. GPS units don't actually calculate your exact position each second. It only calculates the exact position when you first turn it on since that takes about 5 to 30 seconds depending on the position of the satellites. While you're riding every few seconds the GPS unit gets a time a position signal from the satellites but it can't really do a full calculation of your position instantaneously so it uses a simpler algorithm to approximate the position based on the rate of change of the data. The accuracy of the calculation depends on the amount of computing power you have, the amount of satellites in view and the time between points. There is always a trade off between speed and accuracy. The Explore is pretty good at calculating the actual position and speed but not the elevation for some reason. I went up Stillhouse and although the Delorme and Explore showed the same height at the bottom hill by the time I got to the top the Explore was off but 40 feet. It seems the elevation changes a lot slower on the Explore. Just look at how the Explore profile is so much smaller and smoother than the Delorme.
The Explore profile
The Delorme profile
I know all this doesn't really matter but this type of analysis is interesting to me and part of how I get to know and understand the inner workings of the devices I use. In any case because I don't really trust the elevation of the Explore. I will use the elevation from the RideWithGPS instead to for my rides.
The other issue that I found while switching to the Explore is that state of software used to plan a ride has actually taken a step backwords. When I bough the Delorme it came with a software for the PC specifically made to research and plan rides. Setting way points and moving them was a lot easier than using RideWithGPS. I can do things with the Delorme software like show a 3D view of the route that just aren't available now.
Free open source software is good from the point of view that there is a lot of free software available to use but because people don't pay for software any more it is not as sophisticated or easy to use. Of course RideWithGPS is getting better but it is still years behind my current Delorme software. Because of this it will be a while before I can create and upload rides to the Explore as quickly and easily as I could with the Delorme.
For the most part the new Explore is a good replacement for my Delorme and I'm sure in a few more week I will come to rely and trust it as I did with my Delorme.
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