x-ray, I agree with you when you say do not bother with anything that cannot be inverted.
However, I beleive the problem with streaking on negs processed with the FR or Yankee tanks can be resolved with agitation.
I must be getting old as I do now remember using an FR back in the late '70s and to resolve the uneven development problems I changed my agitaion from 10 sec every minute to 5 sec every 30 seconds. It worked well.
I obtained a Johnson cut film tank yesterday. This uses metal film hangers that fit into slots in the tank. It cannot be inverted. I will process some sheets this weekend and leave comment on the results early next week.
Regards and thanks for all the replies.
Peter