The only surplus kit that you would have if you chose to move from Sooloos to Roon would be MC200, TwinStore, MD600 and MC200, this excludes old original Sooloos kit eg: Store one etc, even then you could use the store on most and the endpoint on most so yes there is a loss of function but not complete obsolescence, and of course some will want to stay with Sooloos and so the used market remains.

Trying to be upbeat.

Cheers

Russ