Seen the price on spare parts for these machines?
I'm tempted to buy one and threaten it with dissection should my 560 ever go wrong again.
(Mine was recovered through replacing it's brush assembly.)
Once I had a new assembly, I actually had the courage to operate on the old one, and now have two functioning brush units. It simply got clogged with pet hair right inside the gears. Beyond simple to fix. Yanked it out and put some gear grease in there (vaseline, I think they call it) :D
In a hap-hazard way I'm happy anyway, as I replaced it with a 700 series brush assembly, which is quieter and has covered bearings, so needs cleaning slightly less than the original.
(they do fit, as do the updated aerovac bins, should you want to convert yours to the equivalent of the pet model).
Again, they fit with no modification and outperform the old ones.
In regards to the battery, the system will actually give you a battery error after 1 year even if the battery is functional. You need to open up the bottom plate, then disconnect and reconnect the battery. It will presume you replaced it and off it goes again.
Providing the battery wasn't actually dead that is
I was very impressed with how well the roomba is designed, internally.
It really is built to be maintained and replaced piece by piece as parts fail. Every module pulls out with minimal fuss. Many simply plug and play.
Can't very often say that for many things in these disposable times.
These things are tougher than people give them credit for. They tend to be abandoned as soon as they stall. Roomba has the slightly suspect attitude of re-badging a now very old design and calling it new, but as I mentioned, most parts are interchangeable on most models.
In my experience they're not done if they falter at the first hurdle. In fact they're so tough that IRobot seemed to stop selling the old units as people became wise to the backwards compatibility of the older machines. They even started to pull the lighthouse capability from the 500's as they refurbed them so only the older 500's and higher model 6 and 700's could do it.
Essentially they're all the same machine.
One last thing. Newegg sells almost all the spare parts that IRobot does, only for usually less and with free shipping.
In fact now, now I look again, Now IRobot has discontinued the 500 and lower, they stock more parts than IRobot does too.