  We report transport measurements of composite Fermions at filling factor
$\nu=3/2$ in AlAs quantum wells as a function of strain and temperature. In
this system the composite Fermions possess a valley degree of freedom and show
piezoresistance qualitatively very similar to electrons. The temperature
dependence of the resistance (R) of composite Fermions shows a metallic
behavior (dR/dT > 0) for small values of valley polarization but turns
insulating (dR/dT < 0) as they are driven to full valley polarization. The
results highlight the importance of discrete degrees of freedom in the
transport properties of composite Fermions and the similarity between composite
Fermions and electrons.
