Hi Micky,
I can answer one of your questions.? My understanding is the difference between the Inrad and Collins filters is that the Inrad being a crystal filter has a much steeper skirt at the passband edges, thus a much sharper cutoff.? I think they also have a couple more bandwidth options.? And i've seen mentioned a couple of times that the Inrad filters are a bit larger and must be tucked off to the side inside the rig.? See:
I don't have the SSB filters yet but do have a Collins XF-115C cw filter on the way.? What i'm curious about is if two SSB filters are needed. Can one get away with just one in the RX slot?
Richard