One question spawned the idea of testing Roomba 870 vs 880 — is it rational to choose the device with the long battery life (Roomba 870) or to opt for the large cleaning area (Roomba 880)? However, both models came out of the one factory, have the same engine and navigation.
While testing Roomba 880 vs 870 I've found the difference between their dustbin capacity. Roomba 870's container is 350 ml larger than Roomba 880's one. It obviates the need to waste time for emptying the bin. If to compare their suction — both devices pick up all the debris and dust, as well as the pet hair but not relocate them. However, the manufacturer didn't think it was worth calling the customers about the suction.
Roomba 870's cleaning area is 1000 square feet that are quite enough for one big room or for the small apartments and studios. Roomba 880 can clean 1700 square feet at a time. So, while choosing the device, it is necessary to note the room space.
Roomba 870 versus Roomba 880 is 61 dB versus 66 dB respectively. Roomba 880 really produces a little bit more noise as it was expected. However, the difference is not sufficient — there is no need to wear the headphones while the vacuums are cleaning. They don't impede the communication or watching TV.
During the test IRobot Roomba 870 vs 880, it became clear that 870 has some difficulties with the animal hair on carpets — it clumps the hair together and leaves it behind. The Roomba 880's twin rubber rollers work perfectly on the low-pile carpet. However, both robots can't pick up debris from the mid-pile and long-pile floor coverings that is usual for the budgets vacuums.
The iRobot Roomba 870 is better robot vacuum in this comparison. Check iRobot Roomba 870 price