Absolute best this, absolute best that... Usually, by coincidence what *I* have is absolute best. <excuse the irony>
There is no "absolute best", it depends on what you really need in terms of power, rails, modularity, noise...
PCP&C are good PSUs but I heard one 510W in action and I found it WAY too loud for my taste. Tagans are nothing special IMO. Enermax is OK but many people complain about their total failures with a loud crackling noise which can't be a coincidence... etc. etc.
Try to read a few reviews and get a power supply with 2+ 12V rails, good amps, possibly all the new standards like PCI-E x2, 24-pin and at least 500-550W.
I've had a be quiet! ColorLine 450W German PSU for a year now and it's great. Very stable, solid power, great looks and really quiet. Now, I'm upgrading to an X2 rig with SLI so I need a bit more punch. After doing quite a bit of research and reading/watching reviews, I decided to get a
SilverStone Strider 600W modular PSU. It seems very stable in terms of power delivered, quiet due to one well-controlled 120 mm fan, it has quad 12V rails and is modular which helps you keep your case clean and well-organized inside. Plus, it has the official SLI certificate by nVidia.
I know a guy who bought this PSU a few months ago, and so far it's been working fine. Maybe not "absolute best" but looks good for sure
EDIT: if you decide to get the Strider, just make sure you connect your molexes (4 pin IDE connectors) appropriately, since they seem to be marked quite poorly which made some folks smoke their optical drives or HDDs.