Headphone choices is like asking people what's the best available shoe to consider for puchase. Everyone walks a bit differently and over everchanging terrain where best choice of one shoe is most specific to personal requirements
Some general consideration with few exceptions on headphone choice
1) Most natural sound/imaging are from open types, best isolation/bass is from closed 'can' and sealed in-ear type phones.
EXCEPTIONS: In my experience the most natural sounding 'closed' phone is the long departed Sony MDR-D77. A folding 40mm closed/ported design with very strong tight bass sound, and sense of exceptional wide bandwidth detail; with usual lousy imaging and a pain to put on. Excellent quality-monitoring field phone. Been out of production for 10 years, and I still get email from people wanting a set as there is NO close feature/performance equivalent as yet. Best sounding bass I've yet to hear is from open type MDR-SA3000.
2) Best sound mostly from 40 - 50mm size diaphragms for closed and open dynamic type
3) 24-to-70 ohm/>100dB SPL output for 1 milliwatt input sensitivity is desirable for good performance/loudness with battery/computer powered headphone outputs.
4) Most all headphones WILL more or less sound differently with EACH headphone amplifier that's driving it. Long cords are most usable feature, but present design challenges for lowest distortion phones performance.
5) Model numbers do NOT change, but materials/components to make these models DO CHANGE.
Example is my experience with origininal V6 purchased mid-to early 80's. I loved the natural sounding excellent detail of those phones, expecially if driven with a good amplifier. 10 years later, wanted a second set but every V6 purchased, also tried V600, V7506 Grado SR60, sounded noticeably inferior, at least compared to the definition/clarity still heard on the original V6.
Figured that different V6 components were being used, and it all added up to NOT being a V6 I could live with. Settled for V900 as judged best available, but found this set limited and most useful for having long cord, good isolation sound check purpose, and being much easier to put on/take off than most favored D77 with a bit too short a cord for some purposes.
Later tried and liked very accurate Jecklin electrostatic float phones with 4x4 inch diaphragms, Sony MDR-D77, MDR-F1, MDR-CD2000 in order of acquiring, and currently (in production) MDR-SA3000 as likely one THE best performing open dynamic phones AND the best dollar value ever found.
The SA3000 are now my personal 'fully usable for recording mastering' favorites. Would like to try the costly SA5000 model sometime as the SA1000 model sucked, especially in comparison to the SA3000, so naturally wonder what the SA5000 is like.