I've had a C2500 for about 5 weeks now and love it. I can''t comment MC402 but 2500 is a wonderful addition to my system. The 2500 replaced my long time Musical Fidelity A308 full function pre-amp. I purchased it on this site, new in the box with a 3 year McIntosh Warranty. Please note, some older C2500's may need a "Firmware" update to correct a minor internal DAC/USB issues. The NOS one's you're seeing on this site have the latest "Firmware".
Good Luck!
Good Luck!