How accurate do they need to be? Currently working away around Ireland now, and obviously alot of roads need building. There are a number of A/B and Primary roads there, however do they need touching up?
Looking at the one below, the original road in brown and the edit I have made in blue.
Thoughts? Worth doing or not?
The roads you see were probably paved by a client, and the accuracy of the GPS device will affect how well the roads match the aerials. It’s also possible that the roads were drawn at a low zoom before the aerials were replaced with better ones.
In the specific example you posted, it probably is worthwhile correcting the geometry as you’ve shown. Users probably won’t notice, but it’s nice to get the road accurate if you’re editing it anyway, and it reduces the chance of errors.
Watch out for road developments that may have altered the shape of the road since the aerials were taken. Look at the GPS layer (Shift+G) to see if there are many users along driving the same route.
Thanks Tim, I have been using GPS data for Ireland especially.
Also multiple sources of maps as suggested 
Considering the amount of editing you do, and amount of points you have, you should not be needing to ask such fundamentally basic questions like this. Seriously, I hope your previous editing hasn’t f**ked up the map.
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Hi,
Bottom line, as accurate as they can be.
Whilst GPS signal is a good indicator just as much as “there are lots of arrows and they are mostly pointing that-a-way” you can get wild variations! Wildly inaccurate variations.
Until aerial imagery is to the latest it can be more difficult to make the road/street layout accurate, but if you refer to other aerials and maps you find where the road should go.
So it is important to get them accurate. Shame then that Waze will revert peoples hard work to the sh1t that they cleaned up! But that is another issue.
Des. . .
Another quality reply from xteejx, thanks for your superb input on my thread, it always makes me smile. This Was NOT my original edit and was done by someone NOT GPS, so go and cry to them. I am fixing there mistake.
My points are not from massive edits, I actually sit for hours name roads and so forth, not that I need to explain myself to you!
Anyway I got the replies I required from people who do not utter such negatives!
Thanks Tim and Des.
It’s not a negative, it’s a fact, and one that ANY editor who ranks up so many points should be fully aware of. Sorry if you see that as a negative or bitching or whatever, but the truth remains.