Hello, For my 4350's I currently have Brystons 28bb2's on the bottom and Prima Luna dialogue seven's monos for the rest. Was thinking of changing the tubes for SS. Pros and cons for changing? Brand and size options. I have no problem's but was seeing what was done already. Also have 2397's on top with 2440's &,2405's on separate Prima Luna amp. If this has been discussed already would like the link. Thanks