Hi Paul,
The short answer is that it depends on the school. Some programs are much more interested in your splits - especially quant - because it presents some information about your ability to do the work in core classes. Haas and Sloan are two schools that take a close look. Certainly there are others.
The way a quant split is viewed is also going to depend on your other factors. Someone with hard core finance experience might be okay, while a humanities major who has been working in consumer goods might come under more scrutiny.
The easiest way to solve the problem, of course, is to retake and try to boost both your quant and your overall (20-30 points overall would help a lot for top 20 schools). Short of that, you can also take some legit match classes and perform well. You can also consider something like the CABM, which is a credentialing exam akin to the CAF and which tests core competencies. You can check it out here:
https://www.apbm.org/cabm/.
Hopefully this was helpful. Definitely give us a call at 1.800.925.7737 if you would like to discuss your candidacy or find out about our GMAT and admissions consulting services.
Cheers,
-Adam Hoff, Director of Admissions Consulting