Pay extra to reserve seat?

€2,50 is pretty cheap insurance against having to stand for 6 hours. I'd take it (I did for Cochem to Hannover and Göttingen to Karlsruhe last year).

Make the reservation, it will give you peace of mind and as you say it's only 2.50. I've been on trains where people told me "no problem" plenty of seats and it turned out to be standing room full, and other trains "guaranteed" to be sold-out, near empty.

An advantage of reserving a seat that you do not often see mentioned is that it ensures you will be in a coach that is going to your desination. Long distance trains in Europe often split up with different coaches ending up at different destinations, so it is important that you are in a coach that will end up where you want to go. A reservation ensures you will arrive at the right place.

On long distance trains, I think a reservation is very important. You can ask for a seat with a table even in second-class.

I think it's worth it. On our Norway trip, we had a reservation for our train from Myrdal to Oslo, and it's the only thing that enabled us to get onto the already sold-out train from Flam to Myrdal. Without it, we would have waited for hours for the next train, and missed our Oslo connection. I know it's not the same route that you are taking, but having the reservation assures you that seat, no matter what. You never know!

You guys have convinced me, reservations it is. Thank you!

Hi! You are already convinced, but a tardy vote to confirm your yes! We were told not to reserve before our trip but did anyway! There were people sitting on the floors for hours on our trains over Christmas break 08. So glad we reserved!!