We report on the performance of receive only 300-MHz planar cryogenic (both copper and superconducting) coils for MRI of rat brain at 7 T. The double-sided coils were fabricated by patterning Cu and YBCO on laminate and 0.33 mm thick sapphire substrate, respectively. Practical limits of the performance of the cryocoils (20 mm Cu and 17 mm superconducting) were tested using 3D-RARE, 2D-RARE, and RGB-FA maps recorded with EPI_DTI protocols. Both in-vivo and ex-vivo images were acquired. Twofold SNR gain was achieved at 65K. Cryo-system stability tests with over 11 hours of DTI ex-vivo scanning are presented.