Three years ago I just went for Bose QC-15s (in-canal earbuds weren't an option for me, but might be for you, to change-up 'phones throughout the day. Most are isolating, some are noise-cancelling).
Aside from the noise-canceling, the QC-15 feature I like best after 3 years of semi-daily use is that the cable disconnects smoothly from the headset when stressed, like when you suddenly stand up while forgetting to take off the 'phones. I bought a spare cable, anticipating breakage, but I've never needed it.
These are personal, "pro-sumer" headphones, which are definitely not built to take years of daily recording studio rough-and-tumble step-on, sit-on, throw-around abuse. I've never sat on or stepped on my QC-15s, so I don't know how they'd be affected.
These headphones offer pretty good battery life (I get 40 hours, because I don't crank them loud) and soft circumaural earpads. But even with the light earpad pressure on my big head, I "run hot", so the heat and sweat build-up sometimes bothers me. This is true of all "sealing" headphones. I got some relief with my earpad covers made of stretchy t-shirt fabric. Eyeglass wearers will feel pressure on the frames; I don't know any way around it.
Sound quality is fine for me with good bass and clarity; the sound stage is so quiet it's initially a bit spooky. They're quiet enough and sensitive enough to reveal sonic source faults like my laptop's hisses and crosstalk. I don't know how durable they are against overload: I suspect fairly robust, because the speakers are driven by the 1.5V-powered internal amplifier, not the source (mixer, guitar amp, etc). But I also don't know how protected they are against input signal level over their maximum rated 9 Vrms (http://www.bose.no/NO/no/Images/owners-guide_QuietComfort_15...).
The noise canceling is excellent for my most frequent uses (office, home & planes), and very good for my second-most-frequent uses (public transit, walking). QC-15s do not block people whistling and tiny dogs yapping; I really wish Bose would allow selectable algorithms or firmware updating; I'd pay $50 for that feature.
The earpieces rotate to fold flatter in one's backpack, messenger bag or briefcase (I often roll up the cord and stow it in an earpiece compartment).
I've looked the competition to the QC-15s over the years, but I haven't been moved to switch because the features and performance keeps me satisfied. I might switch if mine broke or were stolen, and some other brand offered cable quick-disconnect and useful selectable algorithms.
The difference (with tax and/or shipping) between your target price point and $300 isn't huge.