Better power cord for Bryston

Stay with the stock cord. Nothing to be gained from snake oil fantasy's.
If you need proof, have a friend swap cords without telling you - as in blind testing - you'll never tell.
The reason so many are afraid of bliond testing is that they'll realize they haven't got a clue.

Despite the naysayers and even Bryston's recommendations, an aftermarket power cord can make a big diffeence in what you hear. I've tried several - Harmonic Tech, DiMarzio, Silver Audio - but have found the best for my 4BST to be the Analysis Plus Power Oval which gives the 4BST greater dynamics. It is an audible and positive difference.
It's worth a try to see if you hear a difference that you like.

I usually agree with the snake oil warnings, too - unless there is a real logical/scientific reason that a product should make a difference. There is an excellent, priced-within-reach power cord that might actually add performance - the Granite Audio 560. It has Double Toroid EMI & RFI Filters (one at each end), is hand built in the U.S., and is shipped already 80% burned-in (so no lame excuses for it's out of the box performance.)

Granite gives you a 30 day no questions asked in-home trial. If there's no audible improvement, you can return it (less shipping and credit card fees, if any).

Here's a reasonably objective review:

http://www.stereotimes.com/cables020402.shtm

or the Granite Audio description:

http://www.graniteaudio.com/cable/page5.html

I'm not affiliated in any way. I have bought one of their Preamps and and one of their power cords here on Audiogon (by posting a Wanted ad and being patient) and think they make great products.

I own 3B SST and I talked to Bryston about this...

It's not that they are saying that using their stock PC is the best.

What they say is that you are not going to gain much by spending $$$ on PC. They say, any good 14AWG with IEC will do good.

I lost my stock PC, so I'm in search of a 'good 14AWG(or better) with IEC' PC...

I'll probably search my email and post it here.