Does any one have experience with a high-end amp switch or the Luxman AS-55

Am I better off just swapping speakerwire bananas at the amp-side? (I know that I need to turn OFF the tubed amp especially when doing so....)

Thanks @br3098 and @cleeds 

The unit's documentation shows it can be used to switch between amps.

@br3098 I appreciate the heads-up on the remote version. I couldn't find the Van Alstine product you described on their website -- is it a custom unit?

Fwiw, I also heard back from Luxman Global who indicated that the switch was indeed good for the L-509x (what else were they going to say!), and that I should use good jumpers/cables.

I was honored to hear from the designer of the Comparator at Van Alstine Audio, and read a few reviews and blogs about the unit. Seems like a great Hifi fit for my needs. In his words,
“A lot of effort has gone into making the ABX box transparent. It is DC coupled from input to output, so there are no coupling capacitors in the design. The only thing in the signal path are relays and an Analog Devices digital potentiometer, which is defined in the Analog Devices data sheet as a "digitally controlled variable resistor". The relays are high capacity 10 amp units, which are many times what is encountered. The digital potentiometer is a necessary evil as it is absolutely imperative that any valid comparison be made at the same volume level.” — Dan Kuechle