I thoroughly agree with the sentiments above. Ultimately, it's a case-by-case judgment call.
One of the primary reasons that online ads have gained such a strong upper hand comes down to the issue of measurement. It tends to be so much easier to track individual users who convert through online advertising, right down to the specific link that delivered them. This data can then be sliced and diced to the nth degree to look for patterns, such as common demographic characteristics and behavioral commonalities; these insights can then be leveraged to further refine your targets and evolve your campaigns, for increasingly stronger results over time. We live in a truly amazing age, in terms of the capabilities now possible for online advertising.
However -- at the end of the day -- effective ad buys are all about finding ways of connecting with target audiences for your product or service. Is there a particular publication or media opportunity that aligns exceptionally well with the audience you're trying to reach, based upon its focus on a specific geographic area, demographic, and / or category of interest? Take a hard look at the cost of that medium, combined with the extent of commitment required for the ad buy and other factors, to determine whether it makes any sense to give it a shot, as part of your overall marketing mix.
Experimentation can yield surprising results sometimes. Try some different approaches; evaluate the results; and then concentrate additional investment on the channels that prove to work best.