TL;DR: The WD62PURZ has a better transfer rate and higher power consumption, probably thanks to a larger cache.
The WD62PURZ spins a little slower than the WD60PURZ, but it has a larger cache. Normally, a higher cache is a sign of an SMR drive, but WD gives no indication of which recording technology both drives use (CMR or SMR).
WD62PURZ specifications are very very close to the newer WD84PURZ- cache, power consumption , weight, MTBF. These are the only 2 drives in Purple product range to use a 5640 RPM spin speed.
|Cameras Supported||Upto 64 HD||Upto 64 HD|
|Max Suistained Transfer rate||185 MB/s||175 MB/s|
|Cache||128 MB||64 MB|
|MTBF||1.0 M Hours||1.0 M Hours|
|Warranty||3 Yrs LTD||3 Yrs LTD|
|Power Average RW||6.2 W||5.3W|
|Weight||1.58 lbs||1.65 lbs|