It's a good offer, and I say that based mostly on the multiplier you are using. I would ask about health coverage. They have a national system here, which is good for emergencies but I would not recommend it for routine care, because it is over-stretched. The cost of living is higher here than most of Europe, but you will be largely insulated from it.

But ultimately, like you said, it is a big change. I would strongly recommend NOT coming solely for the money, especially since you have a good job already. People who do are usually miserable.