Bacharach to St. Goar river cruise

You can take a KD line tour from Bacharach to St Goar.

http://www.k-d.com/englisch/index.html

And, a train back.

http://reiseauskunft.bahn.de/bin/query.exe/en

According to the K-D website, a one way ticket from Bacharach to St. Goar by ship is €9,90. A round trip ticket is €12,10, only €2,20 more. The train back from St. Goar to Bacharach is €3, so its cheaper to buy a round trip ship ticket. However, the train makes the trip from St. Goar to Bacharach in 10 minutes; the ship, against the current take 70 minutes. So is an hour of your time worth 80 cent.

Another thing to think about, you are supposed to get a 20% discount on K-D tickets if you show them a DB ticket used to get there. It doesn't say how far; can it just be from Bacharach to St. Goar? I guess you could ask in Bacharach before you leave. If so, do you want to take the train to St. Goar for €3, then show them the train ticket to get almost €2 off the ship ticket. Then there is the fact that the ship takes 30 minutes longer that way.

Thanks for the information will take your advice re the river cruise and/or train.