I am finally doing a big upgrade from my Echo Audiofire 2 / Grado SR225 (bought in 2001) to a Dragonfly Red + either the Shure SRH1540 or Grado 325e. I have both on order and the question seems to be are the Shures really $150 better to justify the price. Both are considered "top end" of their particular price bracket. Any thoughts? They come tomorrow. and my dad ordered the same ones and we're gonna test them together. Update: This project has taken on new life. I have so far purchased for testing: Headphones: Grado 325e and Shure SRH 1540. This project resulted in the order of: beyerdynamic Amiron and DT990, DT880 Sennheiser 600, 650, 660S, and 700 HIFIMAN SUNDARA and HD-400i's Grado PS500e's w the G Cusions I already own Grado 225 (no i or e!) purchased about 15 years ago and going strong. Ill include them in the mix. DACs: Audioquest DragonFly Red w the USB Jitterbug attachment (will see about this placebo nonsense myself) Chord Mojo Meridian Explorer USB Resonessence Labs HERUS+ Apogee Groove Cambridge DACmagic XS Centrance DACport HD. I will be testing them all together to see what combos come out of it. The DACs replace (hopefully) my trusty old Echo AudioFire 2 which is a Firewire 400 interface. To connect to my MacBook Pro it needs: a FW 400-800 cable, a FW800 to Thunderbolt 2 adapter, then a Thunderbolt 2 adapter to USB-C adapter. And a 12v AC adapter bc the bus no longer supplies enough power after all that adaptation to adequately power the device. It was originally bought to power those Grados and a pair of Swan T200b's that I think arent made anymore but freaking rocked. My desire is to have an adequately mobile listening situation that fits lightly and comfortably in my day backpack that does not require an additional power source/battery. Ill post result and impressions.