I usually transfer money between Finland and Dubai for playing in stock exchange.
Here it is what I have seen with bank transfer.
1. I pay around 25€ when I send money from Finland to Dubai and vice versa.
2. I never tried but I have heard that if you transfer money between two EU countries then you don't have to pay anything (not sure if it is also valid between two different banks)
3. Bank transfer is much secure, and you pay for the security.
4. Euro is better currency, and your receiving account should be able to deal with Euro currency. Contact your bank(s) if you are unsure about it.
5. If you will transfer massively large sums then authorities would like to know about it. Atleast how it goes in Finland.