Ask HN: Devices for sleep monitoring?

I suffer from Delayed Sleep Phase Syndrome and I've been looking for ways to work myself out of it. One of the things I want to try is some sort of alarm tied to my sleep rhythms.

I've been eagerly awaiting the Fitbit Flex for just this reason, however I've seen reviews [0] stating that the wake alarm is nothing more than a fixed time alarm, unlike the Fitbit One. I may end up buying the One, but I wondered if anyone here has a recommendation?

I've seen various mobile apps, but ideally I'd like something attached to me (as that would be more accurate?) I tend to kick things off my bed as well!

Thanks

[0]: http://www.theverge.com/2013/5/6/4303072/fitbit-flex-review