Friends, i'm new here, I'm seeking information about vacuum robots.

I'm from Brazil, and we have limitations to purchase products over $500, and will in general more complicated to import from the U.S., I wondered one roomba but hinder me in some limitations .
And for good or evil is more easier to import from China to Brazil .
Some vacuum robots researched a famous site of china, the dealextreme , all around $200 and Brazil have to pay 100% tax on an imported product, then a product of $200 will cost  twice for me

I want a robot that can clean several rooms of a house, it seems to me that the functionality is called "multi-room navigation" .
For example, I have heard of robots that vacuum only cleaned continuously the same room, or if you wanted it cleaned another room, would have to manually take the unit to another room.
As description of this site:
http://www.intorobotics.com/robotic-vacuum-floor-cleaner-how-it-works-and-design/
" Advanced robotic cleaners have integrated the self -charging mode where the robot memorizes the location where it cleans, return to charging station to recharge the battery, and then return to continue cleaning."

So this list of robots, does anyone have any of these to share experience and/or a video if possible.
The robot can recognize what he has cleared, we will assume that he has cleaned 2 rooms and has gone to auto charge, then when finished charging which robot prevents it from re-clean the same 2 rooms instead of continuing cleaned the rest of the home?

So I looked at the list of robots this site, and here are some models, if anyone has any of these models can give me a feedback if one of its have multi-room navigation and efficiently clean the whole house, plase share your experience.

(placed in front of the ones that interested me and the others after)

http://www.dx.com/p/amtidy-a320-robot-vacuum-sterilize-cleaner-black-310662#.U4uwpSimWHs

http://www.dx.com/p/amtidy-a325-multi-function-24w-2-7-screen-vacuum-cleaning-robot-cleaner-champagne-gold-us-plug-314168#.U4umjiimWHs

http://www.dx.com/p/icubot-007-2-2-lcd-automatic-intelligent-sweeping-robot-vacuum-cleaner-black-149325#.U4umiSimWHs

http://www.dx.com/p/cleanmate-qq5-original-equipment-manufacture-robot-vacuum-cleaner-black-eu-plug-100-220v-306712#.U4um1yimWHs

http://www.dx.com/p/cleanmate-kk8-original-equipment-manufacture-robot-vacuum-cleaner-white-eu-plug-110-220v-316040#.U4uw-CimWHs

http://www.dx.com/p/cleanmate-mt103g-original-equipment-manufacture-robot-vacuum-cleaner-silvery-black-ac-100-220v-316043#.U4uytiimWHt

http://www.dx.com/p/rkk-trv11-25w-smart-rechargeable-sweeping-mopping-robotic-vacuum-cleaner-white-14-4v-316841#.U4uyDyimWHs

http://www.dx.com/p/gentleman-740a-fa-530-home-smart-sweeping-mopping-vacuum-cleaner-black-white-221510#.U4uyHiimWHs

Anyone can help me say something about one of these robots?

Regards