Pros: Bare floors: excellent. Emissions: excellent. Carpet: very-good.
After using the Shark Navigator to vacuum the house a few times, I have come to find that it is a pleasure to use and is suprisingly quiet. Moreover, even in thick deep pile carpet, it picks up fine dust and dirt and traps it incredibly well. It also does a very good job at picking up pet hair.
The first thing one will notice when picking up the Navigator, is that it is suprisingly light weight: it weighs a mere 15 lbs. When turning on the Shark for the first time, note that the power switch has two settings: one for carpet, and one for bare floors.
The bare floor setting omits power to the brushroll: this feature is what makes the Navigator such an excellent vacuum for bare floors, laminate, tile, etc.; whilst the Navigator is also an excellent performer on carpet as well.
The Navigator's ability to omit power to the brushroll, while not exclusive to this particular Shark vacuum, may help to protect against damage to more delicate hard floors such as parquet or wood.
Swivel steering makes the Shark Navigator easy to use when vacuuming around various objects in the room, or up against, or alongside the walls of the room itself. Gently turn the handle of the Navigator, and the entire head of the vacuum will tilt and turn either left or right.
When actually using the Navigator, the balance feels spot on. Pushing the machine fore and aft is easy, and interestingly, there is a suction release vent near the handle. Rather amusingly, the Navigator's suction is so incredibly powerful, that this suction release does indeed make is easier to push on deep pile carpet.
The Navigator's "emissions" are excellent, and this was one of the reasons that the Shark Navigator was purchased. The HEPA filter did a good job of keeping fine allergens out of the air: some vacuums are notorious for the lack of this feature.
The only caveat is that hair tends to get caught in the brushroll. It appeared to be a lot of hair, though I suspect the other brand vacuum that recently "passed away" might have left behind a lot of this hair to clog up the Navigator. Of course, I have seen this on every other vacuum I have ever seen. I recommend not forgetting to pluck this out of the brushroll once in a while.
Rather soothingly, the Shark Navigator ameliorated my allergies, instead of exacerbating them. All of this suction and dust trapping power, without so much noise as to trigger or worsen a migraine headache. I think it is fair to say that this Shark Navigator is an excellent machine, which I heartily recommend.