We did, fall of 2003. We were huge Renaissance fans for their long and unusal itineraries.
Especially in what they're calling the 'penthouse' suites, or above, they're fine. The standard balcony suites have miniscule bathrooms and only one person at a time can pass between the bed and the wall. We've found the staff to be great. The excursions are definately overpriced, but doing your own solves that issue. At least when we were on, the 'tour desk' was of minimal assistance if you weren't going on one of their tours. As far as we're concerned, doing your own research is kind of fun.
Yes, you do sign for everything. No question it's a notch down from RSSC, but not nearly to the mass market lines. We particularly liked the fact that there were no formal nights -- dress was 'country club casual' throughout. We don't feel that took anything away from the experience. They are also open seating for meals, another thing we really like.
The library is wonderful -- lots of books, and a section to leave books you've read and take those others have left. The trivia questions aren't quite so obscure as on RSSC!!
The food is good. I will say that one of our disappointments in our Oceania trip was that we felt the food had definately gone downhill from Renaissance, especially the breads. However others seem to think the food is wonderful -- a mystery to us but a classic example of 'to each his own'. On our trip last fall (with another couple) there was no dinner any of the four of us sought to repeat. We were in a 'Vista Suite' and therefore had unlimited reservations in the two specialty restaurants -- we actually cancelled those reservations toward the end of the trip.
Renaissance was completely non-smoking -- one of the things that drew us to them in the first place. Oceania has tried to 'split the difference' by limiting the areas where smoking is permitted. Sometimes this works, sometimes not. There are those who skirt the rules by smoking on balconies and irritating those in the cabins near them. There are also those who are super-sensitive to the smoke and are unhappy when people are smoking on the designated section of the pool deck.
When you can get a great deal, I'd go for it. Lately most of their prices we've seen have been comparable to RSSC for the cabin we wanted. I must say that we did (on Ren)62 days around South America in one of the standard balcony cabins (the R8 didn't have what's now called 'penthouse') and survived just fine. It was a wonderful trip. But that bathroom is one of the things we remember vividly!!
I can't say we'll never sail them again. Given the right price and itinerary, we would. We don't even consider the large ships. I hope this is of some help!
Betty