Japanese i can understand... But i don't see why anyone would prefer dubs over the original speech (with subs if you need some help).
I think dubs are much better, you don't have the awkwardness of trying to get things in other languages- combined with great voice acting talent. The only times I've ran into bad voice acting talent was in the mid 90s and earlier, and with cheaply translated things. In the early 90s was especially bad, companies would change the names of characters and places because they didn't belive anyone would relate well to someone of a foreign name. This was extremely ironic, because only the most exotic names are considered foreign here, as 98.8% of our population came from immigration. Voice acting got a really bad reputation it can't seem to shake off too well, even when the voices are top notch.
Another reason for this is because people watch shows, and games in the native language (as the dub doesn't make it out first) and become accustomed to that voice, however when their own language comes out it sounds different and there for it doesn't "belong" to the character they had gotten to know so well, and there for shun the voice actor of the language because it's not what they know to be the 'character'. The lip synchronization is a problem for live action films, but unless games or anime are cheaply translated they normally reanimate the mouths to sync it up with the new language. It's a fairly easy process and i'm not sure why every dub company doesn't do it.
Very cheap anime and games are often associated with bad dubs, and for the most part this is a very accurate description from my experience. The publishers are often given a very small budget, and as a consequence they hire the cheapest actor/actress as a means to save money. However, most of these don't even get dubbed, they get subtitled and shipped out via special order or the internet and even then they have very bad subtitles as the translator is often not native to the language, and is paid very little.
For the most part, Japanese/English/German/Spanish voice actors are very much on par with each other (with the exception of the aforementioned circumstances) though i'm not familiar with anything other than German, Spanish, English, and Japanese voice acting talent, so maybe you have a different experience over in Sweden. German may be slightly inferior when it comes to dubbing anime due to it's much smaller fanbase (less money, less to invest, leading to lower quality talent being used)