I used cdwow, the service was great though they didn't get me the choices top of my list so I cancelled.
Then I went to dvd365 service was just as good, bit better at sending high up choices (but never got my first) but one of the dvd's they sent was covered in scratches and marks and had a crack through it so it wouldn't play properly.
Then found a code (FL21) to get three weeks from screenselect, their delivery estimates imply its a two day wait but all dvd's have come in one day so far, they've done a sterling job in sending me my top choices 5 out of 6 so far.
May stay with screenselect but theres so many free trials around its tempting to just work my way through them.