Gerry, I think the PS300's are well worth the expense. they will open your system more than you can imagine. I use them on both the front end and my amps. I also have some vintage United 845 tubes and some G.E. 211 tubes if you are interested. You have not heard your amps if you have not upgraded to these.
PS Audio PS-300 one each for mono amps?
I have a pair of Audio Note Ankuros 75W PSE 845 based tube amps. I am using an Aesthetix Io Phono with volume to drive amps. The Amps drive highly modified Wilson Watt3/Puppy2s. I just got great results from adding a VPI SDS to my Basis TT. What experience have you had with PS-300s, and would the sound improvement going to one for each monos amps be worth it. cheers, GerryM5