I hate to disagree with you Crew and Robert, but I've been using Etymotics for 4 years and absolutely love them. Cheap earbuds don't even come close for isolation and sound quality. You know when you're hearing a truck go by and you can't tell whether you're hearing it in your mix or it's shooting through the sides of your headphones? Now you can tell. And the isolation lets you keep your listening volume quite low to save your hearing, so spikes (especially in conjunction with the nice limiting on modern mixers) don't blast you.
Other benefits - no bald spot from headphones and, you can wear whatever headgear (top hats, helmets) you want.
I've run to the top of mountains with them, dripping sweat and they kept working fine.
The Negatives. You have to keep your ears religiously clean. If you have a lot of wax in your ear you will clog the earbuds, which usually manifests itself as a noticeable loss of gain on one of the sides. The buds come with a cleaning kit, but when you're using them every day, you don't want to be messing with them. I find it easier to keep my ears clean, and then I clean the earbuds when necessary - usually once a month.
You can't hear the director any more if your mic isn't pointed at him/her. The isolation is that good.
Mechanical noise propagating from movement of your body against the wire (and also some jaw movements) can be distracting. I've learned to recognize the distinctive sounds of these movements, but I still get tricked now and then and think - what the heck is that noise? Oh yeah, goretex and zippers rubbing on headphone cabling when I turn my head.
So they are a little different to use than regular headphones, but I'm never going back! All my old headphones are hanging on nails in the basement- they don't even come on jobs any more...
cheers,
Brent Calkin
Ps I mainly do documentary, so my requirements are a little different from a feature boomer, but I would use the etymotics for booming or mixing anything, feature, or run and gun...