The Seagate Barracuda 32MB one will beat the Western Digital in almost all the categories like Burst Rate, Avg Transfer Speeds, Write Speeds, etc.
For more information you can check out this chart from Tom's Hardware:
Tom's Interactive 3.5" Hard Drive Charts
The 500GB WD model u specified is not there but you can get a idea while comparing with an older WD500GB or newer WD 750GB ones.
It beats both of them in most of the categories there.
IMHO, you should go for the
Seagate Barracuda 7200.11 500GB - ST3500320AS model.