I was 5th grade and played a Selmer from Brook Mays in Dallas. In 7th grade, the band director asked for "volunteers" to switch to baritone with immediate advancement into the Marching Band. I volunteered and played Baritone all the way through college and law school. Played at it: 1-2 days a week until age 55. Decided to see if I could make the switch back to trumpet. Rented one and started to work on it. Way too restrictive and so I got a 1914 Holton New Proportion Cornet with a Parduba 5 mpc. After a year felt confident enough to go back to Alumni Band and found a home in the trumpet section.
I play which ever part they need help with 1-4th but no solos. Have to work a little on 2nd but like it best. I find 4th hard because the rhythms are similar but you can't find the melody with a search light.
Just switched to a Leon Merion Jet tone mpc and find a bigger low register and high register of first high D to high F easy enough. Rarely need more than Eb. MPC is a little bigger but still has a relaxed double cup. Old Baritone player finds it comfortable.
Going to be buying Kanstul 731 in a couple of weeks and looking at P-5 mpc.