Agree with tales. I think they'd sell if they were pre-1940's. Anything after that usually doesn't sell. If it does, it's for $.99 or it's a cool car ad. And even the car ads need to be really eye-catching with a really cool picture and not a lot of text. Those only go for $3-$4. 1920's stuff is pretty hot.
People also like to buy ads for antiques that they own. I have only bought one magazine ad and it's for a 1930's street sign I have. I also bought an 1870's newspaper with Thomas Edison and his new phonograph. So, if you have any that mentions popular antiques, they might sell. I actually spent $10 on the street sign one, so if you find a sucker like me you might actually make some decent money.
Also, anything WWII or Vietnam War would probably sell. If it has a cool slogan or cool graphics and says the word "war." Might get $10 or more for those.
I personally thinks it's really sad when magazines get parted out. I'd try to sell them as one piece but mention the ads that are in each magazine and show the coolest ads. Cause once they all get parted out, they can't be put back together again. I imagine people years from now trying to collect 100 year old magazines. I think they'd be pretty ticked off if half of it was gone. Imagine being so excited right now to find a 1905 Sears and Roebuck catalog and then opening it and all of the best parts are gone.