I have a question that some may have the answer. Baltimore Brass has a used Miraphone 56 oval with 5 rotary valves on their web page for sale. When I inquired about the instrument, I asked for the shank size. The response was they tried a small shank and it was too small and the euro didn't go all the way into the receiver. Does anyone have any ideas on this. I would have guessed an euro shank based on my B&S oval. The reason for my interest is certain finger patterns on my compensator are getting increasingly difficult depending on how the arthritis is. I like the B&S oval and do well on a straight 4 up valve non compensator. I'm not driving all the way to Baltimore Brass with no idea what to expect. The front valve Festivo is another possible solution when the time comes. Thanks