I love my SF equipment for two reasons. It all sounds great and is dependable. Second, Chris at Parts ConneXion who designed most of the SF has a full repair and upgrade program. He is knowledgable about the equipment and the TUBES that work best. His upgrade program offers his recent best mods based upon him using any and all parts that are now available. For me, the upgraded stuff is a joy and I have had a part in chosing what works for me. Contact him and he will give you his opinion on what would work best for you.
Denny
Denny