To start, I need to say that I am a fan of the rail pass. My best travel experiences in Europe involve using Eurail passes. There are many different forms of rail passes and for the most part, I have used them all. So let me go through the advantages and disadvantages of the different types of Eurail passes.
The Global Rail Pass
This was the pass I got when I was backpacking across Europe for three months. I think the biggest disadvantage is the price. This is the by far most expensive pass. It also has different prices for if you are 25 and under which is a second class ticket and 26 and over which is a first class ticket. But it gets you a train ticket to almost anywhere in Europe, ferries and other discounted tickets as well. It also means that if the weather is bad in France but great in Italy, get up that day and go to Italy, it does not matter you have a ticket. But what I love about this pass is the freedom of travel that it gives.
I like to stay in regional areas and take day trips everyday instead of packing my stuff up and going to a new location. Some examples of this was I was staying in Vienna and I really wanted to go to Budapest. I knew little of Budapest at the time and was not sure I really wanted to stay there. So I took my rail-pass and got on a train at 6:00 in the morning and arrived by 9:30 in the morning, spent the day in Budapest then grabbed my rail-pass and took the train back to Vienna and was back by 9:00 at night. A perfect introduction to Budapest.
While I enjoyed the unlimited travel of a global rail pass, it is not for everyone. First, it is very expensive. With the cost of budget airfares and deals you can get on single tickets, it is not necessary a financial deal. Secondly, it is only useful it you plan to take a lot of trains. Buying a rail pass for two weeks and only taking 5 trains is not worth your money, there other options for taking less trains. Lastly, many fast trains charge supplemental fees for eurail passengers. I was shocked to find out how much more it cost to take a night train or a fast train in France. If long fast trains is how you are planning to travel, check the supplemental fees before traveling.
The Saver Pass
Rail passes can be bought in many different forms. I have bought them in three different ways. The global continuous pass is the pass which I took on a trip where I backpacked across Europe for three months, and have explained in this article. The next one is the Saver Pass. The Saver Pass is the same as any other rail pass that you can get, but the difference is you can save 15% if you travel with 2-5 people. The big caution about this is you have to travel together at all times. If you buy a saver pass with your friend and you want to do a day trip and your friend wants to go somewhere else, you cannot use the pass. Neither of you can as it is only valid if both of you are present. So only get this if you know you are going to be traveling together at all times on the trains.
Regional Rail Passes
You can also buy regional rail passes. This is what most people will probably buy. Most people do not plan on going to enough countries to merit the high cost of the global rail passes. But if you still want the flexibility of a rail pass, you can buy either regional or a country specific pass. I recently bought a Eurail Benelux-Germany Pass that was a saver pass ( traveled with my husband) it was for 5 days of travel over two months. This was great for us because it gave us the flexibility to not be completely tied to travel days. If we were not taking some long train rides, it would not be worth it. We also spent the $50 extra a person for the first class tickets because it really is worth it if you have the extra money. The regional or country specific passes are available in 1st or 2nd class for adults unlike the global passes. While we might have saved money if we bought our tickets separately rather than a rail pass, it was worth it for the flexibility.
So yes, I am a big fan of rail passes. Not necessarily for the cost savings, but for the comfort, peace of mind and flexibility of travel.