What should small companies use Microsoft Bing ad or Google Adwords?

Data released yesterday by small business (SMB) marketing platform Pricing Engine argues, as a number of others have in the past, that Bing ads are a “more efficient” buy than Google AdWords. While Google has more search volume and higher CTRs, Bing emerges as a lower cost source of leads for SMBs according to the company’s analysis.
(See also, AdGooroo’s comparison of Google AdWords vs. Yahoo-Bing ad performance in six verticals.)
Pricing Engine looked at its own data from hundreds of small business accounts. It found that CTRs were marginally higher on Google but CPCs were much higher.

Source: Pricing Engine small business accounts analysis
Accordingly, the SMB spend was determined by Pricing Engine to be “more efficient” on Bing. While big brands may favor the higher query volume on Google, SMBs don’t demand or frankly need the same kind of scale. Indeed, in some cases, significant scale can create fulfillment problems for SMBs.
The following chart shows the average monthly AdWords spend by business category among Pricing Engine’s SMB clients:

Source: Pricing Engine small business accounts analysis
This next graphic below reflects a comparison between the average CTR and CPC (for Pricing Engine clients) by business category for Google AdWords.

Attorney services saw the most expensive clicks and the largest gap between CTR and CPC. Automotive by contrast was almost perfectly balanced.