Best rail option Stuttgart to Salzburg

ICEs are the top-of-the-line express trains in Germany - very fast and smooth. But ECs are no slouch, either. I'd look at the time and price to decide. As for class, unless you are really obese, 2nd class should be fine on either type of train. I don't feel the extra cost of first class is worth it.

Thank you!
I think we should be able to squeeze into regular seats, even after several days of beer and wurst consumption.

Both trains are fine, it's a nice trip. The Austrian RailJet (Abbreviated RJ) is also a fine train that makes that trip, all of the trains will be listed on bahn.com. 1st class is nice but not worth the extra money unless there's a significant issue with 2nd class seats. Even in 2nd class, ICE is nice. :)

I had to laugh a bit when reading Lee's comments. On German trains 1st class is not only chosen by overweight people (even though the seats are much wider) but also by those who do not wish to be surrounded by hordes of screaming children running up and down the aisles for an entire 5 hours trip or so. Also in 1st class they serve food and beverages on the seat which means you do not have to get up and maybe leave your luggage unattended just in order to get a coffee or sandwich. First class is less full on a friday afternoon (while in 2nd class people will even sit on the floors, in the aisles, even block the bathrooms etc. which means you cannot possible leave your own seat during the entire journey). If an EC train is operated by DB German Rail expect very old carriages with worn-out seats (1980s color scheme and never been renovated since). If it's operated by ÖBB Austrian Rail it can actually be quite nice and modern. On ICE trains in 1st class you have one power outlet underneath every seat. In 2nd class you have one outlet for two seats. On EC trains you usually don't have any. Personally I find train rides great to recharge my iPhone e.g....

Vielen dank, all! I think the privacy and guaranteed seating might be worth it, since this is the longest leg of our trip. And since I just realized that the price quoted on bahn.com was for 2 passengers (thought it was per passenger), am feeling flush. Now, one more question - Do we go for the "compartment" or "compartment with tables?" I really appreciate all of your advice.
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James, when was the last time you were on a RJ? The last 3 times I've taken them, they've been beautiful, brand-new looking trains. First class in them was amazing but second class was pretty nice too. This was the line that goes from Budapest to Munich (in one case all the way to Stuttgart). Maybe they use older RJ trains within Austria, I don't know. I like sitting with a table, it makes eating and drinking easier, and gives you a place to write postcards, etc. I also think that reservations for long trips are a good idea. It's not very expensive, so you might as well.

If privacy is what you want then go for compartment. I always book compartment with table (Abteil mit Tisch) which means you get one of the window seats in a compartment with only 6 seats in total. If you book Abteil mit Tisch for both of you you'll get the two window seats facing each other across a table. In my opinion that's the perfect seat on a train. You can keep your hand luggage on the middle seat and the aisle seat might or might not be taken by someone else (usually from STR to MUC only though)...

Thank you for the thoughtful and useful responses! Looks like we're going with the direct (EC), 1st class and a compartment on this one. We'll get to try out the ICE during another journey.
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