Adwords - exact vs phrase

Hi,
I hope this is the right place for this question.
I've been running an Adwords campaign for a month and am now looking at refining it to make it more efficient with the data I have collected.
My question is what is best practice for bidding on phrase and exact match.
Lets say my keyword is "sausages". The majority of my sales from looking in GA from from the keywords "sausage" and "sausages", none from phrase matches such as "where can I buy sausages" etc.
In my adwords I had [sausages], [sausage],"sausage" and "sausages".
My average CPC is higher for the exact match.
I'm not sure what do to based on the above - drop the exact or drop the phrase match?
For instance since CPC is higher for exact I could drop that and still pick it up via phrase match which has the lower CPC? Or when I'm competing with a phrase match against someone with an exact match will I drop down?
Any guidance appreciated!
Thanks