VVS operational use of B-F I-207 or Kocherigin Di-6?

[Harold K]

Can anyone shed some light on whether these two biplanes saw any combat use with the VVS?
Internet/print resources I've seen are scanty and somewhat contradictory. Some references state that one or two of the few Borovkov-Florov I-207s built saw service in the Winter War against Finland. I've read that the Kocherigin Di-6 was used against the Japanese during the Nomonhan/Khalkin Gol "incident"; I've also read that they definitely were NOT used in that conflict. I have also seen a sketchy reference or two to the Di-6 serving in the ground attack role at the time Barbarossa began.
I'm trying to determine whether or not to include models of either of these a/c in my collection; my main criterion is whether or not a given aircraft was actually used operationally.