I received my se425s after sending my 6 year old E4Cs into Shure... Awesome CS, BTW. The sound on the SCL4 seems to be better overall. The se425s completely fall apart on cymbals and snares - most of the time you can barely hear cymbals. When you can they sound like fingers-on-a-chalkboard. I'm listening to CDs and high-quality AAC. Another thing is that the sound isn't as clear, it is muffled on many songs. It almost sounds like a busted speaker but I don't think I actually have one.
I have to turn these up fairly loud to hear all the sound then things start to pop but it snaps so tight and screechy that it is difficult to listen too. All the sounds don't seem to blend together smoothly its like they are all disconnected parts and distant. They sound like a Tin-Can where the SCL4s sounded full and natural. I'm not sure if that is what they are supposed to sound like or not. Songs that sounded perfect on the SCL4s sound completely different on the se425s. Electronic music seems to fair better than studio recorded instruments.
Any thoughts would be appreciated.