MY FIRST ROOMBA WORKED FOR A COUPLE OF MONTHS AND THEN THE WHEELS STOPPED MOVING. THEY SENT ME A NEW ONE AND #2 LASTED A FEW MONTHS AND THEN IT STARTED DOING WHAT THEY CALL THE CIRLCE DANCE. THEY SENT ME A NEW ONE AND #3 NEVER WORKED. STRAIGHT OUT OF THE BOX AND IT WOULD DO NOTHTING. I KNOW HAVE MY #4 AND IT HAS STARTED DOING THE CIRCLE DANCE. JUST CALLED CUSTOMER SERVICE AND WAS INFORMED THAT IT IS NOW OUT OF WARRANTY BUT I CAN GET A REPLACEMENT FOR MORE MONEY.AFTER THE ORIGINAL HUGE EXPENSE AND THE HISTORY OF THIS PRODUCT THERE IS NO WAY I WILL SPEND MORE MONEY FOR A ITEM THAT DOES NOT WORK CORRECTLY. I WILL NEVER BUY ANOTHER PRODUCT FROM THEM AND AM INFORMING EVERYONE I KNOW OF THE PROBLEMS.