What kinda product are you sending?
2 sided? Postcard? TriFold?
Had to say it is a 50/50.
I had considered asking one of my agents, or my carpet install/retail guy if they wants space for a percent. But my concern is. Getting the client to flip to the other side, or look past whatever ad they see 1st or heading.
We only have a faction of a second to grab the potential client, so that keeps me from getting to excited from sharing space.
Now if I were doing an envelope that had to be opened Heck yeah..
I'd like to know how it works for you, I'd suggest a separate sample of just you and you alone, compare calls.