Plasmatico, I don't have experience of the options but I think the options stack up like this: (I stand to be corected if I've got it wrong smile )

From a sound quality perspective, the Mac Mini and SB3 are on a par, using digital outputs. Differences relate to functionality, not sound. The Transporter offers high quality DACs and power supplies and is an option for those who want SB funtionality with analogue, not digital, throughput.

Regards,
Steve

Steve