Pros: Good SQ overall, Not too expensive, Comfortable, Portable, Great Isolation, Easy to drive (no amp required)
Cons: Recessed mids, Short cable, Wide headband can make you look goofy
This quick review is done after a few hours of listening. I bought them from B&H for the decent sum of 150$. If you've done your research you'll find out that Ultrasone HPs are known for their deep, strong bass, slightly recessed mids, and somewhat shrill/metallic highs. Some like it, some don't. I do. They also require anywhere between 100-300 hours of burn in, from what I've read around here. I listen to them straight out of my Dell Vostro V131, Clip+, and iPod 2nd gen + Fiio E6 via LOD (the headphone jack doesn't work well anymore.) with 320kbps files.
On first impression, these do have good base extension and impact, although less than what I've expected from reading the comments here. Bassheads should probably take a look at the bassier HFI-580. I was looking for a versatile headphones that could play well with the different genres I listen to (modern rock, EDM, jazz, classic rock plus movies). These hit the nail right on the head. I prefer them to my previous versatile HP, the venerable ATH-M50, because they have a slightly better soundstage, though keep in mind that they're still closed can. As for the mids, they're slightly recessed. That would be one of the 780's only faults. Since they're easy to drive, I don't listen to them at high volume so the shrill/bright highs don't bother me at all. I actually think they bring out the drums nicely in some cymbal-happy rock songs. Overall, I'd say that the 780 are okay to listen to during long sessions (I always take a break after 1hr, don't abuse your ears, people!) Although people who like to listen at high volume may find the bright highs to hurt their ears.
I bought the revised version of the HFI-780 and when I read around the forums there weren't a lot of reviews for the newer model. The revised version comes with a very short cable (1m) which is annoyingly slightly too short. They do come with a very long 4m extension cable. The pads on the earcups and the headband are also different. They're now softer and don't hurt my ears. They're more comfortable than the M50 pads (they don't feel like sandpaper.) So don't worry, they're comfortable. I ordered the DT250 pads in case but they mess up the sound (less bass) at the expense of comfort. They're gonna be returned. The headband applies some pressure on the top of the head but I think the padding was also changed on this version. Finally, these HP isolate very well, making them perfect for the library/airplane. Sound leakage is almost non-existent, well done Ultrasone!
If you're someone who's self conscious, these HP might not be for you (your loss). The wide headband design sticks out which can look a bit goofy. Although I do find the silver earcups design very nice. It's up to you.
Overall, I do recommend these headphones for first time listeners looking to take a plunge into the audiophile world.