Well, the old adage "you get what you pay for" has been proven time and again, has it not?
But I truly believe that with Contiki, you get at least a little more than what you pay for :)
The hotels themselves were clean, and only one was so far out of the city as to be inconvenient, that one being the Ibis Schiphol in Amsterdam. I will admit that the Hotel Lowengraben in Lucerne (it's an old jail) was creepy and that it was annoying to have to pack an overnight bag for it, though.
The bus was a newer one and very clean as well, and our bus driver, Henk, was pretty cool. I wouldn't want to have to navigate that bus through the Alps, that's for sure! The only bad thing was that the seats were really small. As a fairly tall woman (5'8"), when the person in front of me put their seat all the way back I had to sit with my legs spread in order to fit, which got a little old on some of the longer bus rides.
The included meals were what is to be expected. The breakfasts in Amsterdam and Barcelona were pretty darn good, and Paris and Chamonix were okay as well. Nice and Lucerne were questionable. For the dinners, most of them were at least edible, except for the one in Lucerne, which I won't even get into.
The optionals were mostly really great. The canal cruise in Amsterdam was awesome because it included unlimited drinks and gave you a neat view of the city...the Sea Palace dinner actually got canceled because hardly anyone signed up for it...the Nouvelle Eve cabaret show in Paris was fun, had great food, and if you were sweet about it they even gave you a little more free wine than they were supposed to ;o)...the lake cruise in Lucerne was okay--really cheap drinks, and it was cool to see more of the lake than we would have seen had we not gone on it, but it was rainy and cold there so that kind of sucked...the Aguille de Midi cable car would have been cool had it not been so foggy at the top (we couldn't see more than a few feet in front of us, so it turned out to be kind of a waste of money), but had it not been foggy it would have been amazing (I will warn that even I, who has been up fairly high in the Rockies here in the States, got really lightheaded at the top)...the Monaco dinner was just that, a dinner, but the food was really, really good, so I recommend that as well...and finally, the Flamenco show in Barcelona was a lot of fun (neither the show nor the food was as good as the cabaret in Paris, but it was still worth the money).
The "informal" optionals were basically just the tour guide taking us out places that aren't technically Contiki sanctioned, the first being the "cultural show" (read: sex show) in Amsterdam. That show itself was, well, weird--basically just a bunch of not really attractive people having completely dispassionate sex on stage, but it's one of those things that it's cool to say you saw ;o) Our tour guide also took us to bars in different places--this Irish bar/club sort of place next to the Moulin Rouge in Montmartre in Paris was tons of fun, but expensive...the "pub crawl" in Chamonix was lots of fun because the places we went were less touristy...Wayne's in Nice was interesting, but a little too crowded for my taste (and also still expensive)...the sangria bar just off La Ramblas in Barcelona was cheap but a little dodgy, and pretty boring (no music, and we got shushed when we tried to play drinking games)...and last but not least, Baja on the beach in Barcelona was a blast, even on a Sunday night!
Our tour guide, Kristy, was absolutely wonderful. She was nice, approachable, and I feel like she really went out of her way to do many different things so that everyone could have a good time at one point or another. She was also great at getting us to do and see as much as possible in the very limited time we had in most of the cities.
The people on the tour were...well...interesting. We had a lot of couples, somewhere between 8 and 10, but most of them were lots of fun. We had three women that were a bit older and kind of separated themselves from the group, whereas most of the couples were friendly and open and went out with us almost every night. I would say that 70% of the people on our tour were from Australia...there was only something like 8-10 Americans and maybe 7 Canadians! No problem with that, though--it was awesome to meet people from all over the world!
As a whole, I had the time of my life on my Amsterdam to Barcelona tour, and I would do a Contiki again in a heartbeat. I would definitely recommend it for younger people who are outgoing and want to have a lot of fun, but if you get easily frustrated with loud and crazy Australians it might not be for you ;o)