My hair is extremely thick and heavy. It also has a slight wave to it. If I don't blow dry my hair with a round brush, I end up with lifeless, limp hair - especially if it's hot outside or if there's any hint of humidity in the air. My hair is also about chin-length, so it's not like I can just pull my hair up in a pony tail. If my hair goes limp, there's nothing I can really do about it.
My hair routine used to take about 30 mins because I had to use both the dryer and the round brush. It took so long! This little gadget cuts my time in half. And if I bundle my hair up in a towel and let it sit that way for about 10 mins, it's even faster. It also gives my hair INCREDIBLE body and volume. It's SO easy to use too. Kind of like a comb or a brush...or even a flat iron. You just section out a section of hair and slowly "brush" (underneath the section to slightly curl it under or over top of the section to flip it up) the hair. You only have to go over the section a few times before it dries it. You can also adjust the amount of tension that the "brush" uses to pull your hair out straight.
I've used all of those "hot air brushes" including "professional" ones and this is the best I've ever used. For one thing, it heats up a lot hotter than those types of brushes. The air coming out of it is more forceful and stronger. And the tension discs make it alot easier to get the hair drier and straighter in as little amount of time as possible.
The only issue I had was that it doesn't completely get rid of my slight wave. It's not that big of a deal, since it doesn't bother me a whole lot. I think this product is mostly made for people who are looking for more body and volume in their straight or slightly wavy hair. If you have curlier hair, you'll probably have to try the full sized Infinity blow dryer tool.
Bottom line - this is the easiest way to get the effect of a blowout. If you use a round brush and a blow dryer, you could not get the same effect in the same amount of time with the same amount of work. It's also easy to travel with - all you have to do is wind up the cord and toss it in your bag. It doesn't take up much space, unlike a blow dryer, and you don't have to bring other tools like brushes. I know this product may seem kind of expensive, but it's worth it. If you can afford it, buy it!
My Experience: I put myself at a 5 because of the following reasons: I managed a Hair Salon for over a year. This required A LOT of knowledge of hair products and hair stylers. I know that this product isn't necessarily considered "professional" but it works better than a lot of professional brand products that are sold to the general public.