The price is right....or is it?

[nat8808]

On the other hand, a balance control often involves the signal going through two pots of some kind or at least a secondary shunt? (p.s. I've no idea how people implement balance controls).

I've what looks like a home-made valve pre kit from the 80s and originally it had dual mono volume controls but the owner then reconfigured it for convenience to stereo and balance - essentially just wired one pot in series with the other as per the different functions dictate. Sonically daft IMO. DNM has the same dual control philosophy - less circuitry or few components in the signal path at the expense of convenience.

On stepped v continuous controls: You can't really implement dual controls which double as a balance control with stepped attenuators without giving such a rough balance control as to be fairly useless - it simply wouldn't pass the reviewers tests without being shouted about etc etc.

So to use a stepped control and be commercially viable, they'd have to also include a balance control. Therefore sonically the stepped + continuous balance control would have to outperform a good continuous on it's own. i.e. not just a straight comparison