MN6 is much better than MN5. (.. that is just my opinion ...)
The Irland Maps are also better now. The M50 is in in its full length available, just some Exits are still not fully implemented.
The rural side roads also improved, I just can say this from my experience with the far South West around Bantry.
It is a big improvement, but still not comparable with the Continent.
Maybe they do not get the Information from OSI.
I had problems with the miniSD which was shiped by Navigon (Not a very fast SD Card). It is sitting very loose in the Adapter, that resulted in a couple of corupted and lost files in MN6/Settings/ . I don't like these Adaptors at all.
I copied everything, the whole Europe map material, onto a fast (150x) SD card.
A second SD Card holds just the British Isles which I use constantly.
All this works fine for me....