The pass gives you 5 days of “free travel” — midnight to midnight and you can take as many trains as you like during that 24 hour period. A special rule (“7:00 PM rule”) means that most overnight trains only count as one rail day even though they cover 2 calendar days. However, you can travel as much as you like, you just have to buy a ticket if you don’t use your railpass. You’ve only got 3 trips that are covered by a railpass in your itinerary (Eurostar, the chunnel train isn’t covered), so 5 days is plenty.Also, you’re only traveling in 3 “countries” (Belgium, Netherlands and Luxembourg counts as 1 country “Benelux”). The pass will sometimes help with local transportation, but it probably won’t cover all your local transportation needs. For example, part of the RER (regional light rail in Paris) is covered, but not the part in the center of town and the buses and metro (traditional subway) you’ll generally be taking to get around aren’t covered. The S-bahn in Munich (suburban light rail) is covered but not the U-bahn (traditional subway). But it’s not an issue with a flexipass as you wouldn’t want to use a day of the pass (maybe worth $35 to 50) to cover a few euros worth of subways and buses. Obviously you’ve got some reason for that much time in Brussels — anything over 2 days would be overkill for me. I’d do an overnight trip to Bruges and a day trip to Bastogne or somewhere else in the Ardennes. Depending on what you work out for your flights to/from Europe (into London, out of Paris — or vice versa, into Amsterdam, out of Paris or London) I would look at re-arranging to take advantage of direct Eurostar routes — Brussels/London and Paris/London. Rail passes cost the same and come with the same bonuses no matter where you buy them. Sometimes there are minor differences in shipping costs or extra freebies provided by the travel agent. All things being generally equal, why not buy here and give your business to the people who kindly sponsor the site where your questions are getting answered? As a member I think you get $10 off the regular price.