pros/cons of frequent flier tickets

Once you have the FF ticket there is no difference between a FF and a regular ticket. Getting the ticket is the problem, not using it.

CL, do you have a credit card with Delta's name on it?
You might get enough miles from a signup bonus to get your seat- check on Delta's website or google a frequent flyer forum. I have had a lot of success with getting free tickets (on Continental & Delta), but it is not worth buying an upgrade to biz or first unless you can book the upgrade with miles.I would pay cash for the slight extra cost for the premium economy seats once you have your FFseats in hand. I love first and biz but can survive for about 14 hours in the back if no one is seated next to me! Your seat selection is not affected on an American carrier by it being free. Delta also has the miles & cash payment plan if you are a Delta credit cardholder. There is a formula for deciding when it's cost effective for buying miles on one of the FF forums on a cents-per-mile basis. I think FF tickets are flexible because you can for a fee of usually $150, redeposit your miles rather than let the airline hold your money for a year.

Other headaches with FF programs are blackout dates, and the fact that most airlines limit the number of frequent flier seats on their flights. So it can be difficult to get FF tickets for the dates and times you want. There can also be deadlines for using your miles. When you're in an FF program, it's important to keep your boarding passes until you're sure your miles have been credited. If the airline messes up & fails to give you your credit (happens more than you think, especially with 'partner' airlines), the boarding pass is the only proof most will accept.

United will now allow using FF miles for one leg of a trip and cash for the other leg. The trip needs to be planned at one time (miles plus money) because they have a ridiculous system of charging horribly high fees for one-way travel. On the down side, FF miles needed now = 60,000 RT to Europe. (Those flights used to be 50,000.) Some trips require more FF miles. I guess this covers what could be blackout dates otherwise. At least, if you have plenty of FF miles available, you can fly almost any date. I was able to combine United FF miles with Continental FF miles and have enough for a "free" trip RT to Heathrow next spring. Taxes still came to about $170. It's good to make reservations way in advance, if possible.
You will have a reasonable choice of seats if you get your reservations early. Otherwise, schedules may be lousy with one or two stops on the way to Europe, and/or you may get the worst seat on the plane. And don't expect any upgrades to become available while flying on a FF ticket. These comments are based on my experiences flying United Airlines.

When I first started flying to europe in the late 90's I signed up with UAL and at that time it was pretty easy to buy an upgradable ticket and use miles to fly business class. However in the past 5 years this is very difficult unless you buy your tickets 10 months in advance and be flexable. My friends are AA flyers and they usually have to take a round about way to reach their destination often time taking 4 different flights to go from LAX to europe.
I have become fed up with ff miles and just buy the business class tickets.

Hi CL. No, no major pros or cons to using FF miles. Currently you can buy this tix for about $1230, so just a question of 1) willing to turn in the miles to save $650 vs.
2) keep the miles, pay the $1230 and use the miles in a different way (i.e. 2 or 3 domestic round trips? free round trip for diffferent dates / cities in Europe? etc.) of course the $1230 cash price is as of today; it will go up and down over time...

Sigh. Lots of inaccurate, incomplete, and misleading information posted here - as it always is in any thread about FF miles. Look: using FF miles is in many ways as complicated (maybe more so) than making decisions about your European trip. This website is a wonderful resource for info on traveling to Europe. It's full of great, accurate information - on that. I love it. But it is a terrible source of consistent misinformation about using FF miles. Asking a general question like "what are the pros and cons of FF tickets" is like asking, "what are hotels like in Europe?" The best advice I can give you is to go to the place where people make a serious study of using FF miles (google Flyertalk), and take what's said here with a big grain of salt, at best. Some suggestions: unless you just need a very small amount of miles fast, spending real money to buy FF miles is almost always a very poor investment. There are soooo many easy ways to load up on FF miles for free or nearly free that it's not very smart to buy them. Ignore anything that anyone says about "blackout dates" - that term a marketing scam intended to fool rubes. That said, there ARE serious restrictions on getting tickets (but not "blackout dates"). You seem to want to go from Portland to Prague/Munich and back. There are a thousand ways to do that. Only looking at ways to do it on Delta (why?) is foolish and limiting. Honestly, there are so many variables and subtleties in the mix. You can not expect to get the information you need here. You need to go to the right source, and be prepared to invest a little of your time learning how things work. There are no simple answers to the questions you pose above - at least not without understanding how things work. Sorry if this is not what you wanted to hear, but it's the truth.

My wife and I used miles, 60,000 each in June 2009. Yes we did have to book in Aug 2008, but we were able to get the dates and airports we requested. We just booked another trip to Italy/Greece/ Istanbul using miles (60,000 each) for travel in June 2012. We will arrive in Milan instead of Pisa, but for a free ticket a short train ride is worth it. All trips were with US Air miles. On our 2009 trip part of our trip was on Lufthansa, they upgraded us to business class from Chicago to Frankfurt. We gave up our seats to keep a family together, so it does happen. Most airlines will hold you free ticket for 48 hours, do not buy your miles until you have the flight you want. Call 2x a day and if they are do not have one leg you need, ask if they will check with 'inventory' to see if they will release a seat. Good luck,
Mike

Decide when your trip will be before where and then every day check possible itineraries on the airline website. Obviously look as far out as possible. Check out FlyerTalk.com boards for more ideas. I am.a miles junkie.