The maker was touting that their pattern cleaning was more efficient than random cleaning
They had a very competitive price.
I found that it does a good job of cleaning, but I have had to get used to moving EVERYTHING that might get in its way.
The boundary markers that it came with are pretty much useless since it has a tendency to push them around.
It sometimes has a hard time moving from hardwood floors to the rugs, over heater vents and over our air return.
I had vacuumed the area the day before it was delivered,then ran it the next day. It picked up a fair amount of dirt, but not enough to fill the 0.6 liter dust catcher.
It has a good battery that I charged overnight before the first use. It ran for at least two hours.
I emailed their support, but have not gotten an answer from them yet.