I know this is a old post but decided I'd comment just in case someone needs a answer to this question so I'll give my 2cents?? I have a cleaning service and have used many vacuums. I own the first dyson that came out and clean for 2 other people that have 2 different kinds of dysons and I can tell you all of them are not the same. They all do the same kind of job but ones heavier, one has a longer cord, exc....My husbands grandmother owns a rainbow and a dyson. My dad has a dyson and a shark. When it comes to the vaccums that do not lose their suction such as dyson and shark and ones that don't blow dust out everywhere it comes down to personal preference because the shark and the dyson pick up exactly the same. The rainbow picks up basically the same as both the shark and dyson. The difference in the rainbow and the other 2 is that the rainbow is a lot of unnecessary work. Why go thru the headache of using the rainbow when u can get the same results from one u just plug in the wall and go?!? There are many vaccums out there but what's important is the suction and keeping the suction and keeping the air u breath clean in the process. Some vaccums suck good but end up spitting it out somewhere else. The shark and dyson keep its suction. The rainbow does most of the time. The shark and dysons keep dust and allergens out of the air and the rainbow seems to as well. The main goal of a vaccum is picking up trash and dust from your floor and keeping it in canister onces it's there. If u have a vaccum that does that I say u have a good vaccum. I personally think the orange dyson ( the very first one that came out) is the best vaccum but that's my personal preference. I'd also like to add that I have had my orange dyson for 10 years and it's like new. Like I said the other dysons have features I don't care for. The rainbow is a good vaccum as far as I can tell but who wants to have to pull that heavy thing around. I cant tell u how many times that big canister has got up the speed and rolled into the back of my heels or slammed into the wall. U have to fill it up with water then when your done u gotta find somewhere to pour that nasty stuff out then wash out the bowl. U gotta change hoses according to the floor your cleaning. The dyson and shark just has a button u press to change floors. If u live in a 2 story then u are in for a huge backache getting that rainbow up and down the stairs. The rainbow is just a huge pain in the butt I can live without. I can get the same results and better with the shark and dyson. That's just my opinion and personal preference though!!!