I've been using a SE-40 for over a year and I've been very happy with it. It's a great amp for the money. I haven't expiermented with many cables. I'm using Monster Cable for speaker wire and an Esoteric between the preamp and amp. I hope to upgrade soon. I've had some luck changing the driver tubes. Right now I have a Brimar 6sn7gty(cv1988) in V1 and a TungSol 6sn7gtb in V2, It sounds great. I'm just using the stock Sovtek power tubes, but I've heard that Svetlana power tubes sound better. Good luck.