Yes, you can use City Navigator on both your laptop with nRoute and on your Colorado. Two things to be aware of:
City Navigator requires an unlock code. So when you buy City Navigator buy it for the Colorado and buy the DVD version. When you install it to your PC from the DVD, it will install into Mapsource on the PC. Then you use Mapsource to unlock it. Then you can download all or part of the City Navigator maps to your Colorado and they will work on it because the maps are unlocked to the Colorado.
That part is all pretty straightforward. The next part takes a bit of work.
The new format of the City Navigator maps doesn't work in nRoute. So after they are installed on your PC you will need to run them through a program called ReverseMapConverter. That will convert the City Navigator maps back to the old format, which will work with nRoute.
If you like nRoute, I think you will find this process the easiest. If you buy Mobile PC you will have a number of difficulties. But there are a couple that would be a major factor.
You will not be able to use the maps on the Colorado. Period. You would still need to buy City Navigator maps for the Colorado, if you want to use those maps on both the Colorado and your laptop.
You might need some additional software to use the Colorado with Mobile PC.
If you want to use your Colorado as the GPS receiver for your laptop, the software-only version of Mobile PC that you would need is not particularly friendly with Garmin receivers. It works great with almost any non-Garmin receiver you can find. But for some reason Garmin has messed it up so it refuses to work with many of their own receviers, especially the newer models. I have an eTrex Legend HCx and a GPS10x bluetooth. Mobile PC won't use either of them. It finds them just fine but refuses to use them. Your Colorado is even newer so I'm sure Mobile PC software-only version won't use it.
There are a couple of ways to get around it. One is that there are a couple of software solutions to make it work.
The other is that you could buy the version of Mobile PC that comes with its own GPS Receiver.
EDIT: Oops, I see Terry gave you a nice short version of what I said. What he said.
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