I’m not sure that I accept the criticism that anything made by Martin after 200xxx is of poor quality. I’m fairly sure that most of us with day jobs just don’t have the ability to understand the differences between trumpets. To be clear, we might notice differences in timbre, slotting, or intonation, but ultimately we’ll compensate one way or another in order to get the sound we want, but we won’t completely understand exactly how we modify our approach in order get that sound.
As an example, a year or so ago I came across a Martin Committee from the early 60s….post 200xxx. I have a 56 Large Bore Deluxe with which I am fairly familiar. When I switch from my Committee to my Benge, or my Yamaha, I certainly can hear and feel differences in the horns, but does that imply poor quality? If a horn requires that you move more air, of pay more attention to intonation or articulation, but in doing so produces a better quality of sound, does that make it poorer quality?
I made a video, it’s around here somewhere, of me playing my 56 Committee back to back with the later model horn. I don’t recall them feeling much different as far as blow goes, and the sound was similar too.
Finally, there’s little doubt that quality control in modern horns far surpasses that of anything made in the 50s, 60s, or even 70s. So there may be a wider range of “quality” in any vintage horn, but that doesn’t mean they were all crap.
Ultimately all that matters is what you like, which will inevitably be the horn that requires the least amount of work to produce the sound you want.
-tj