I'll start by saying that I have never been a Bose fan. I generally think their products are overpriced and not always better than brands you can find for much less. They advertise A LOT which always makes me suspect of a brand...if they are so good, the products shouldn't need so much advertisement. With that said, these are fantastic and worth every penny.I actually bought these for my wife but I've had a pair for over a year. She wasn't really interested in having a pair no matter how good I said they were.So I bought her a pair for our anniversary and she is SUPER happy with them and wishes she had gotten them sooner (I was right for once!)These are the best headphone purchase I've ever made and I have bought quite a few - not all of them have been cheapies (several pricey Etymotic and Shure models).The active noise canceling is superb and works great on a plane, in a car, at the office, etc. Even if you aren't playing music, it gives you utter silence from background noise unless it's really loud. Sound quality is great as well and the battery has lasted at least 6 hours continuous and would likely go longer but I've never used them for longer periods than that without charging.The ear tips are very comfy and do not come off in your ear or accidentally fall off and roll under something like some other brands. They fit on securely so you never have to worry about losing them. This has long been an issue for me with other brands...I'd arrive at my destination and pull the headphone out to use them and voila, one of the buds is mussing. I don't miss those days at all!They seem to be very durable. I carry them back and forth to work, on trips, etc and no issues with wires fraying, or coming loose, or anything like that. Can't say the same for some of the aforementioned expensive models I've had in the past. Every last one of those broke down in some fashion after less than a year of use.I only have 2 small nitpicks so my rating would actually be 4.5 stars since there's room for improvement:1) the on/off switch is raised (as opposed to recessed) which makes it easy to slide on and off which is a good thing. However, it also seems to get turned on accidentally while in my bag every once and a while so I go to use them and they are dead :( It would be better it it were recessed with a small raised bar in the center that was only as high as the unit itself so it would still be easy to switch but not be as susceptible to accidental movement. The good new is, even when the battery is dead, you can still use them. There is just no active noise reduction and the sound quality diminishes greatly.2) the unit on the cord which houses the battery and the switch is kinda clunky and gets in the way sometimes. It also makes it tough to wear for any kind of physical activity. I understand they have to put the battery somewhere so it can't really be helped but maybe it can be streamlined into a cylinder shape to make it less obtrusive.I guess I could complain that they are little spendy and rarely go on sale but as I said, I really feel like they are good enough to justify the price.My only worry now is that the new iPhones are supposed to be coming out without the tradition headphone jack which means I won't be able to use them with my iPhone unless there is some sort of adapter. :(