You got it backwards dude, nbadraft.net is know for poor rankings. DX is much better at doing their homework on players.
Seemed like the last 3 or so years I had been following nbadraft that they were pretty close on all the top 20 picks. There was a bit of a jumbled mess from 10-20, but pretty much all the players that were listed were drafted in the top 20.
Draftexpress was pretty spot on for 2007 though. Both are good sites, I just prefer nbadraft. the only thing I would change with nbadraft is their writeup. Sometimes they lack writing something up for a year or two on each player.
Something both sites kind of suck at are position needs for each team. They never consider which team needs what, and put whoever they want.
I feel the Kings fans are better at writing up a mock draft for our own team than either..