Not 100% sure myself (if they are level or not) but I do like No.2, the reflections are lovely as are the colours in the leaves below the water. I also like the B&W conversion on No.3, works well with the mist.
Not quite as keen on 5 or 6, they just don't grab me like the others.
What camera did you use (sorry can't accress Flickr at work as I.T. block access!). What I did discover the other day was that my D7000 has a vitual horizon you can bring up on the LCD. I'll never have a wonkey horizon again!