Roomba: It does the work!
This year we've got for Christmas our very first home robot. I was a bit reluctant to buy an expensive item just to figure out later it might work elsewhere but not at our home. This has not been the case. Since day one, our Roomba performed nicely and the only trouble we've got is that it does not like our low-profile doorstoppers.
We've made the comparison between them amount of dirt picked up by us and the one we remove from Roomba. I've to say the robot wins in the "who picked more dirt" game. The only extra work we're doing in preparation for Roomba to clean a room is to remove as many objects as possible that might interfere (i.e. chairs, trash bins, etc). I'd say it's been money well spent (as far as the robot keeps the performance level for a couple of years).
What is a plus is that the robot may return to the charge station by itself (sometimes) when battery needs to be recharged. I'd day this is not a feature to trust on, as I'm afraid it may not work in some cases. Apparently if it detects the proximity of the recharging station while the battery is low, then it will go to be recharged. But I won't say it will actively try to find the recharge station by roaming around the house. That means that sometimes Roomba may just power itself off somewhere in the house after doing its job for quite a while (I'd say it may run for more than an hour before battery is depleted).
We all find amusing just looking at Roomba do the cleaning and, even more interesting is the docking process (the return to the charge station to be recharged). The not so good point is that is noisy: You do not want to have in the living room when you're watching TV.