There are many different part numbers for this unit. The later the letter, the newer spec the unit. For example, the earlier AA and AB units were not compatible with the MDI kits.
DAB is digital radio broadcast. I don't know whether you have DAB in Finland or not, or whether you'll actually have DAB coverage where you live I'm afraid. That's something you'd have to check with your radio transmissions authority over there.
There are also some bluetooth model RCD510 units I've seen, but again they may be chinese spec imports. I'm not sure what unit you'd be best getting, as my knowledge of them is kinda used up right here. However, if you find one, feel free to post up the part number and someone should be able to tell you a bit about that particular one.