In my businesses in Texas, we have mostly used bright four color postcards with a very professional "We Buy Your House" messaging.

I am working on writing my own copy for my DM postcard to absentee owners.

Ordered postcards through yellowletters, had calls answered by PatLlive using Account Closed Part 1 script(modified slightly).  

Or are we talking about their actual postcards and/or mailing service as well?

I just mailed 175 postcards.

Joe Thompson there are some good replies on this thread:DIRECT MAIL PostCards on the BiggerPockets forumshttp://www.biggerpockets.com/forums/93/topics/471189-direct-mail-postcardsI agree with Ori Skloot it really depends if time or money is a more limited resource.

Todays drop of mail:479 Postcards for NODs1750 Postcards for groups 1 and 2144 Yellow Letters InheritedBTW the reason for the PCs is that it happens to be the Postcard Touch time for both NODs and groups 1 and 2.Here is the PC

I have read about people doing very well just mailing postcards.

I sent out the mail in the form of physical post cards. 

I sent out postcards last week to a list of code violations and I also started a fb ad campaign around certain zip codes.