Pros: Sound quality, Isolation, Comfort and fit, Durability, Hard shell case, Price
Cons: If used with portable or casual home use, needs replacement cable
I realize it is a bit of apples vs oranges, but I will compare these to the Sennheiser HD 600 sound, since I sometimes use those to mix recordings with, and many know their sound. Assuming good sources and amplification, the HD 380 pro sounds as balanced through the mids and highs as the HD 600. Both are what most would consider neutral, or flat, with the HD 600s being ever so slightly polite, or veiled, or easy on the ears in the highs. The HD 380 pros have a slightly more upfront treble, but they are as natural and as detailed as the HD 600s. With the HD 380 Pro's closed design, the spaciousness of the HD 600's open design is replaced with a more intimate sound stage, or isolated effect of closed design. Resolution of fine detail in the mids and highs is outstanding in both of these cans, but is just slightly better in the HD 380 pros. I can hear more of what is in thick mixes with it.
Now about the bass. The bass in both cans is good and tight, and in the right balance to the rest of the music. The bass in the HD 380 pro is far more extended into the lowest octaves and is clean and tight way down to the sub bass 20 Hz. The bass in the HD 600s is good but slightly loose down to around 40 Hz, but even there it is starting to roll off a tad, and continues to to the point that it isn't accurate enough to monitor a mix well enough in the lowest octave, though it isn't missed much on a lot of music, such as classical or acoustic jazz or folk, that doesn't have much energy down there. Overall, the HD 380 pro is clean and accurate and distortion free all across the entire audible frequencies, and is able to offer quick transients and dynamic impact not available with the HD 600s. Part of this is due to the difference between closed and open design, the improved angle of the driver to the ear with the HD 380s, and the easier to drive impedance of the HD 380s, but for bass impact down low, the closed design is superior.
The HD 380 pros are very comfortable, with the perfect clamping pressure, and large deep ear chambers that will accommodate the biggest ears on the biggest heads comfortably for hours on end. They stay put and in position on your head even if you are moving around a lot. They make a very good seal and isolate you from outside sound better than any other non-active noise reducing headphones. At the same time they also leak the least amount of sound, which is essential in live recording, and a huge plus for listening in noisy environments, or in quiet places where you don't want others to be bothered with your program. They come with a good coiled cord, which is perfect in the studio, but a bit clunky and heavy for home and portable use. Fortunately, the cable is easily replaceable and after market cables specially designed for these cans are available in four different lengths for around $30 at Amazon. Just search "replacement cable for Sennheiser HD 380 Pro" there at Amazon. At this time, Sennheiser doesn't offer the straight cables, but I have purchased the cables through Amazon, and they are great braided cables with top notch plugs and strain relief.
They come with a handsome hard shell case, are built to take rough treatment and survive, and look good for headphones of this size, They are the best value in high quality headphones at only $105 now at Amazon. 5 stars!