Pros: Excellent sound stage, glorious brass, easy to drive from a portable player, swapable cabling
Cons: isolation and leakage not to CIEM standard
I've found myself unable to use custom IEMs and needed to find some high quality portables for my three hours a day on public transport. After lots of research and some excellent help from assorted head-fiers, I settled on these.
My music tends to be expansive american 20th century (Copland, Ives, Gershwin), more minimal (Reich, Stockhausen, Ligeti), and female vocal (Dusty, Roberta Flack).
I've been listening to the Sig Pro non-stop since they arrived, and for my head they are as comfortable as any I've worn. My main home headphones are LCD-2 and I love their sound which seems to work very well for my preferred listening, I didn't expect the new ones to match the LCDs, and they don't, quite. But they are remarkably close. They have quite an open feel for a closed headphone and the Copland and Gershwin feel very spacious. I'm not a major bass head, but I dug out some meatloaf and felt really nice, absolutely bassy enough for me but still strong on the voice. Brass sounds really good, bold and bright - just the way I like it.
Next step, going portable. This was the main reason for buying them so I really needed them to behave nicely with my IBasso DX-100. And they really do. To my ears, they actually work better with the DX-100 than the LCD-2s. They more than match my ACS-T1 CIEMs for comfort and clearly exceed them for sound quality on everything I've listened to so far. They only fall short of my perfect portable headphones in two respects: sound isolation and noise leakage. They aren't bad at all but they don't compare to CIEMs (I guess nothing you stick on your head as opposed to in your ears is going to...).
The overall package you get for your money is nicely assembled. The case has a sturdy feel and enough space for my DX-100; the interchangeable cables are useful, as I prefer shorter for commuting and longer when I'm settled somewhere; and I hope to get hold of the cable with the inline microphone to try to use them as a phone headset.
All in all I love them, and if I was only allowed one pear of headphones for all my needs (perish the thought), I'd pick these.