Optimizing Ads : CTR & Cost/Conv.

We consistently test new ad copy in our client's accounts. We typically review performance of these ads in 14 and 30 days and make a judgement call regarding which ads we're going to keep, followed up with additional testing of new ad copy.

We've had a few instances lately where one ad in particular has a higher CTR (sometimes rather drastic) but a lower Conv. Rate and higher Cost/Conv. Here's an example:

Ad #1:
Clicks: 16
Impressions: 353
CTR: 4.53%
Conversions: 2
Cost/Conv.: $39.92
Conv. Rate: 12.50%

Ad #2:
Clicks: 13
Impressions: 355
CTR: 3.66%
Conversions: 3
Cost/Conv.: $20.38
Conv. Rate: 23.08%

I'm conflicted as to which ad we should move forward with. Maybe there's not even enough data here (I'd love to hear your opinions).

Reasons to go with Ad #1:
If we go with Ad #1 that has a higher CTR we should theoretically see an improvement in our Quality Scores which should result in a lower Avg. CPC and Cost/Conv. We won't know if this will result in a Cost/Conv. that's comparable to Ad #2.

Reasons to go with Ad #2:
Going with Ad #2 we should see a lower Cost/Conv. I'm not sure how likely it is that this lower Cost/Conv. will continue, but it seems to be the most obvious choice financially.

What would you suggest? :confused: