Even IF they get delivered, you have to view it as you react yourself when you go to the front door and look down at that pile of stuff the ppostman has just shoved through the letterbox. It contains:
A) Your "proper" mail, stuff actually addressed to you from companies you deal with, or personal corrpondance etc etc.
B) All the other "cr@p"
Most of us pick up everything that comes through the door and sort it into 'A' pile and 'B' pile. Guess how much notice the customer is taking of your leaflet, in the 'B' pile along with the 6 other pieces of advertising? None, because it all gets shoved in the recycling box and they open their 'A' pile letters instead!
Now, consider you come home, the door mat is clear and there is ONE leaflet left trapped in the flap of your letterbox. You're at least going to have a quick glance over it as you walk to the bin, aren't you?
I shelled out on a pre-Xmas Royal Mail door drop. I knew it wouldn't work and it didn't. I took one booking for January, which she then cancelled a few days later. But I can now say with confidence do not waste your money on it. I didn't lose a fortune, but it would have been a nice weekend away.