We purchased the Irobot Braava Jet M6 about a year after purchasing the Irobot J7+ to clean highly polished Porcelain floors similar to that shown in Figure MP1. We have tried the Braava several times prior to this review using the three modes of (i) mapping, (ii) dry mopping, and (iii) wet mopping with only filtered water. The most interesting result compares the Braava dry mopping with the J7+ ‘vacuuming’ of roughly 600 square feet of polished porcelain (to be described below). Mapping: The M6 does a good adequate job of mapping the house although it has some inaccuracy in the placement of doors and walls – the J7+ provides much more accurate maps. For example, the M6 erringly inserted a small pathway between our adjacent laundry and guest bath rooms. We able to correct the map by inserting a boundary line using the map editing mode on the iphone. Some of the mapping errors most likely occur because when the M6 backs into an object or partially runs up on a rug, the M6 spins its drive wheels while the M6 platform remains in place. The counting of wheel rotations can result in distance error when the wheels rotate without moving the platform. Several wheel revolutions (without platform motion might produce 6inches of error in the distance. Additionally, whereas the J7+ uses a camera to accurately map, the M6 apparently uses sensors such as an xyz accelerometer to measure changes in speed, a gyroscope to measure changes in platform angle, and a sensor to count wheel rotations to determine movement distance. Consumer grade accelerometers and gyroscopes have some inherent error. But, nevertheless, the M6 does a good job mapping so long as boundary lines are added by using the software. Docking station: The M6 returns properly to its docking base for charging despite the base being relatively close to walls and objects. Our base sits about 1 foot from a wall and washing machine. Works great. However, we did find the unit became confused and only docked with difficulty when the docking station was within an inch or two of a side wall. Presumably the M6 detected light reflected from the wall rather than that from the docking station. Just to be clear, the docking work well with the 1 foot spacing. Spots: We tried the M6 wet mopping using only filtered/distilled water. Once the mop encountered dirt or grime, the remain portions of the floor became spotted. Presumably, a neutral PH cleaning solution would help with the problem but any time water remains on the floor to evaporate, any dissolved minerals etc. will show as spots. The wheels did not leave streaks beyond the first foot or two at the start. This review will be updated as we deal with the spots. Dry mopping: We were very impressed with the dry mopping ability of the Braava M6. First, the J7+ ‘vacuumed’ about 600 square feet of polished porcelain; it removed particles and dust as much as possible. We next ran the M6 through the same 600sf. Figure MP2 shows that the M6 removed dust and hair left behind by the J7+. This confirms our previous test where the J7+ ‘vacuumed’ about a 1000sf of polished porcelain and then, about 1day later, the M6 dry mopped the same 1000sf – see MP3. It should be pointed out that the M6 could not remove larger particles than dust or hair. We recommend the Irobot Braava M6. While some features can be improve, they would perhaps double the cost of the unit to bring it on par with the J7+. The M6 does a good job and worth the money.