I'm sure both are outstanding units. I have been an ARC user on and off since the original SP-3. However, I presently use the VTL 7.5III preamp and am completely taken by its performance. Two considerations were the drivers for me. First, the ARC is not really ideal to drive a 10K load with significant current capabilities over long cable distances which I needed for my Spectral 400's amps. (The Mosfet output of the VTL's on the other hand, can drive anything. It has balls galore.). Secondly, I like the reliability of the hybrid design of the VTL and that I can easily tailor my sound by rolling only 2 driver tubes (ECC82 NOS Telefunken's are my preferred tube). I don't think you can go wrong with either. I would however be curious to learn the results of a well-done shoot-out between them.