Rob,
I have used a Bryston 4BST and a Spectron Musician II with the Gold is. I found the Spectron to be head and shoulders above the Bryston in terms of overall sound quality, plus, its a more powerful amp. Im still using the Spectron, but with a pair of much higher priced speakers (Silverline LaFolias) and I still love this amp! My preamp is a VAC Vintage MKIII linestage and Im using a Cary 306/200 CD. I would recommend a very good tube preamp with any solid state amp used with these speakers. Good Luck!
Jim
PS: IMO, for what the Golds cost, they are a great speaker!