Every time I use DP there's always excuses and about how busy they are (last order over 5 weeks to delivery) . The artwork thing seemed to be their only real selling point and they are moaning about that now.
When I need new leaflets I groan thinking of going through all that again. Started printing my own, cheaper and faster.
Paul is right about print carrier, but you need a proven design or it's straight to the recycle bin.