From a technical standpoint, it stands to reason that it would depend primarily on the design of the particular piece of equipment the cord is supplying power to (its sensitivity to electro-magnetic and radio frequency interference on its ac input; its degree of isolation between ac neutral and signal ground, etc.), and also on the purity of your particular incoming ac. So I don't think you can rely on the experiences of others; trial and error is probably the only way to tell.
Regards,
-- Al
Regards,
-- Al