After much consideration and much good feedback from fellow colleagues, finally I get myself a Roomba, the model 555 which is local model number that similar to 560 except the accessories in the box. This 555 does not have extra filter and comes with only 1 virtual wall unit.
Got this from an eBayer whose got lucky by winning it at a luckydraw, he is selling for $500 while the retail at $898.
Happy I got this model and its a hardworking machine which you can schedule it to vacuum your house when your are not at home so that when you get home, your floor is sparkling (almost) clean .
Its so smart that its even return to its homebase for recharge when finish vacuuming
Just let it run for the first time after > 16hours of charging and Voila!!! the floor is as clean as after mopping...
Edit: Warranty covered till: Oct 14, 2012