CI /Performance question
 

Hi All I am a A 320 pilot.
My question is related to Cruze Level.
Suppose your final cruze level as per your CFP is level 360.
You are cleared FL 320 and do not expect further climb for say 70 to 100 Nm.
What is better performance /fuel conservation vise changing the Cruze Altitude to get the Cruze speed for these 70 to 100 Nm with Alt Cruze on the FMA or mentaning climb speed with Alt on the FMA ?