While searching for updates I found out that Nokia gives 1-week free navigation licenses.
One can be obtained from here.
Instructions: a mobile phone has to be supplied and a serial key is sent as an sms that has to be inputted in Nokia Maps. Unfortunatelly +359 (Bulgaria's country code) is not supported (but Romania is) so I used a friend's phone.
Yesterday I tested the thing and it's amazing. The routes it calculates are better than Garmin's ones. Interacting with the software is so much better, especially browsing the map - awesome. There is voice guiding in Bulgarian.
The generally good thing with Nokia Maps is that it's free (the software). There are a lot of maps that are also free. Only the routing capability has to be purchased - it's not very cheap.
Unfortunately their maps are really poor. Bulgaria's map is only 4 megabytes. The Bolkans' map is like 40-50 if I recall correctly.