"Headphones" have been posted here enough to turn it into "Headache".
No offense, but what led you to whittle it down to those 2?
What about Shure, Sennheiser, AKG, or Grado?
What are you wanting to do withese cans - track or mix?

I personally don't mind the 770's but I've never bothered to purchase any. I still utilize my KOSS Pro 4AA's & Sennheiser HD 414/424/545/280's. I've used more of those 770's with the microphone boom on intercom systems when running a camera for television in noisy environments. So, you need to go and listen to the ones you want to purchase, from the same CD & the same amplifier. Otherwise, I might suggest a Chevrolet.

Have you considered a Chrysler? Maybe a Porsche instead of the Chevrolet or the Chrysler? I've also heard the Toyotas & Hondas are also good. So which one should I get?

Enough already. These won't be your first and they won't be your last. They're like green stamps. Remember Green stamps? You could get an OSTER blender or even a vibrator by the same company. So what would work better for you?

I really miss my OSTER vibrator you plug into the wall. So much faster and more effective than the battery-operated types. I know... TMI
Mx. Remy Ann David