Cartridge Limitations or Break In?

I've just gotten going with my first TT and cartridge, a Shure M97xe. So far I'm really impressed with it for the price ($56 or so). The only place where I'm having some problems with it is in certain tones and higher notes. In particular muted trumpets - Miles Davis at the Blackhawk just fell apart - and with the reverberations on some loud vibraphone passages - Milt Jackson on a couple of Pablo recordings. I've read that that this, and other cartridges, need some time to break in to smooth out. Is that what I'm experiencing here or am I discovering the difference between an inexpensive cartridge and pricier model?

Still sounds bloody good for the money.