tym, exactly why I’ve just got myself something with maps on!
The 200 is great when everything’s exactly as expected, but sometimes a little more info can be very handy indeed!
Google image search for “garmin edge 200 screenshots” to see what it gives you. I bought mine for a SDW in a day ride. Only really wanted a computer to show progress, av. speed, but discounts and a summer cashback meant the 200 was only £70. Very handy indeed to have a check on the bars and not to keep stopping, getting the map out to make sure you’ve not missed a sign post.
Another thought is that it depends what you want out of a GPS. If you want to leave the map in the bag and just ride, then it will do that. It depends on how big the route and how much extra navigation you need to do if you modify your route.
You can always print a picture of the route, or even take a picture of the map on your phone. If you need too cut a slice of the route off, you can figure out where you are, based on how far you’ve come, the little map on the 200 will zoom out when you stop to show you roughly where you are on it, and then you can strike off east, west whatever.