I bought the Blue Pearl in October of 2006 and used it for about a month getting the pool balanced and ready to close. I opened about a month ago so I've now used it for another month getting the pool clean and ready for the season. Here is my initial review after an admittedly short period of ownership:
Pros: The pearl is fast and cleans the pool very effectively in 3 hours time. It climbs the walls and, for the most part, covers the pool well. It has sponge rollers as opposed to many of the other robots that use a rubber-type roller. The sponge rollers seem to do a really good job of getting the dirt and debris off the floor and into the vacuum. The filter bag can be a little messy to clean but otherwise is easy to use. I've heard other people complain of their cleaners getting stuck on various things but mine has no problem with the stairs or drains in my 18 x 36 rectangle pool.
Cons: I noticed that the Pearl would occasionally spend an inordinate amount of time in the deep end and I've heard this is a common issue with many cleaners. After observing the cleaner when it was on the slope, I noticed that it was losing traction when trying to make the turns that it's randomly programmed to make and this was causing it to go right back to the deep end when it might otherwise be headed up the slope. Since then, I have tinkered with the settings of the handle and it seems to have improved considerably although I'm not quite sure how yet. I'm sure someone else with more experience may be able to explain how the handle adjustments could impact this issue. The only other thing I've noticed is that I wish the cord were a little more flexible and resistant to kinks. I try to counteract this as much as possible by stretching the cord out in the water when I'm coiling it up to put away and making sure the twist is out of the cord as I wrap it.
Overall, I have been very satisfied with the Blue Pearl and would recommend it to others looking for a good robot without the astronomical price. I paid app. $600 for mine.
Hopefully others with more time and experience with the Blue Pearl will chime in to add to the review.