Ok lets start out with this. I have had seven roombas. From the simple red ones to the more advanced 560, the scooba, and I now have the 650. One thing you can count on with irobot is the higher the model number the higher the price and yes features. I feel there comes a point when the features get in the way of the product and we may be approaching that timeline.
The red simple models are great. Do they pickup everything, no. Are they pretty reliable, yes. I have one that is five or six years old and all I have done is replace the battery. One other red one just went insane and died after two years.
The scooba… well that was just a mess. It tried hard but could tell even when new it was just waiting to freak out and break down. Gave it away couldnt face the future loss as you do tend to get attached to them slinking around the house.
The 560 was a complete dog. It started having nervous issues after only two months then the battery went. Replaced battery then all the warning issues began. This one talks to you so she was always telling me her problems and what she needed and what she cant do. Im guessing just like a real maid that is high strung and bad temperament. Dead with the fatal error code 3 AHHHHHHHHH!!!!!!!!! Well that was three hundred bucks I will never see again. (insert sound of toilet flush).
So it looks like all the new models die just after the warranty is up by a few days. So now I have three dead ones the others were trashed. The quality does not seem to be improving as fast as the complications. The more advanced the higher the chance of failure.
The newest model, 650, is a little heavier than the 560 here that I have (may she rest in peace). Everything about the 560 is the same as the 650. The 650 has better hair pickup than the 560 and a few more bells and whistles but it should for four hundred dollars. With the reliability track record I dont think i would spend he dinero on a 650 and just get a working 560. Find it on sale if you must. Just not comfortable with the longevity any more and customer service at irobot while friendly is not much help. There are lots of forums that will help you trouble shoot your issues. Maybe too many.
My 650 so far its working as intended. We shall see how long it lasts. Old red roomba and 560 sitting in garage awaiting burial. Still have one red going strong just had to replace the battery. (ebay seems to be about the best deal for batteries, sometimes an Amazon seller has some at a good price, its all timing.)
In the end I think irobot should FOCUS on making them better vacuums and less on new features and gimmicks. They could do it if they want to, and make them less complicated so they will last longer.