Anyone ever experiment w/ better circuit breakers?

Are you aware that the National Electrical Code (N.E.C.) makes it clear that the breaker used in an electrical panel shall be the same brand as the panel itself? That doesn't leave you with to many options. You could up-grade to a bolt in breaker panel if you had some extra money to throw away. That's what we use in Commercial and Industrial installations.

If you want to spend the money, go for a panel with copper bus and bolt on breakers.

Glen's statement is correct that the brand of the breaker panel normally dictates the brand of breaker. Bolt-in would provide a more solid connection, but there's another alternative.
Take a giant step backwards in time & install a small fused disconnect branch circuit panel, paralleled off your mains, before power even reaches the main disconnect breaker. Source your dedicated line(s) from fuses, which sound better than any circuit breaker. Old ceramic fuses sound best but the new plastic ones are OK too. Just don't use glass fuses, they're not nearly as smooth sounding.

Bob is right as far as my ears are concerned. I threw all circuit breakers out and installed ceramic fuses. Much better punch and dynamics. Cheers,

Would someone like to set some percentages on this tweak? After (a) dedicated circuits, (b) hospital grade wall outlets and high quality in-wall cable, (c) a/c line filters, and (d) audiophile grade power cords everywhere (not to mention the Quietline shunt filters in every unused outlet), am I REALLY going to be able to hear what changing the circuit breakers does??