Ok, I have already reviewed this product and found it to have good performance overall , Upright mode performance is probably best in the industry, StickMode and Handheld Mode is acceptable for a reason. This vacuum actually has three motors, I believe. One to turn the rollers of the floor unit, a powerful suction motor to power the Upright and another small suction motor to power the handled, up top, which also powers the Stick Mode. The suction from the big canister is very strong, industry leading strong, no complaints. The suction and performance of the small suction motor on top of the Handheld is just acceptable, not going to say is bad, as it does get the job done.
2 Major Flaw Issues: The big canister does not have a fully sealed system when you remove it, and a pile of dirt will fall out of it, not just tiny particles but a big thick pile of dirt and debris. This is a clear design flaw when removing the large canister, because it's a key and special part of the whole Shark Transformer idea and process. Shark should have installed a retractable cover/seal/door that closes each time the large canister is removed, and opens with you put it back. The other major issue is the small handheld's small canister, it's a very inefficient system that is supposed to collect most of the dirt and debris and then be emptied out by the suction system of the vacuum's large canister. When I saw the video on Youtube and this site, I loved the idea, but learned the hard way it's a very inefficient system that (very loudly) probably only gets about 50% of the dirt and debris out of the handheld,while there is a small hole by the filter that collects alot of dirt and debris directly on the filter that the whole suction process from the large canister does not clean out at all, leaving a shockingly dirty filter that can only be cleaned properly, by the difficult process of taking it apart then clean it with a small brush which Shark does not provide but needs to. Summary: The vacuums performance is good but the dirt and debri canister system is so bad, it brings a 4 to 5 star vacuum all the way down to just one star, and I'm not being unfair, BOTH canister systems is A CLEAR MALFUNCTION, poorly sealed and inefficient.