The headphones are pretty good but I rarely use them for stupid reasons. As I write this I'm listening to internet radio with my AKG 512s (which are my portable set) whilst sat at my work desk, and to my right the Sennheisers are parked on top of my plush cacodemon. What a waste of money.
The Scarlett didn't work out particularly great, but you couldn't use it as a pre-amp anyway so it wouldn't help you.