Selecting headphones and a headphone amp

AKG K-1000. DO (!) a quick search on these, and you will understand. I did and became very interested and mindset for a pair, someday. Well, I found a pair from an excellent member here, and received them two days ago. Suggested 8 watts min, as per my research. My 300b amps are too far apart for their wiring, so I tried with my 45 amps, and they are more than enough on quiet music, Excellent!! Bass..?? not too lacking. 300b's were my initial intent. I will try them soon! Your amplification has plenty oomph+. No extra amp ($$) needed... Good luck

The MOST important thing in headphones is COMFORT. If they are uncomfortable does not matter what they sound like.

I own the senn hd 650, AKG K702 and Beyer HT 880 pro.
they sound great and are very comfortable. You forget you have them on.

For portable use, I also own, and highly recommend, the Koss Sportapro and senn px100.

I also own the Grado sr60. I didn't like them. Not very comfortable. They are the entry model for Grado. They currently reside in the closet. Maybe one half hour of use.

Well, I wouldn't call Grado particularly comfortable, especially that cable in front of you sometimes trying to get in your face, but they are not uncomfortable either.
Perfect comfort is not everything though unless you listen for hours straight. I never listen for long because music playing in my head puts me to sleep quite quickly. But Grado could improve comfort, that's for sure.

I would find a place where you can check out the AKG K or Q 701's or the K702's. I think they're the best value and can be had new for about $250 new in some cases. OR if you're willing to waste some money on the shipping if you don't like them, there's a set of K701's ($195) and Q701's ($210) for sale here right now. They're already broken in, and would let you make a more accurate decision as to whether or not the sound is for you. (If you can live with the green color I would get the Q701's as you can switch out cords and AKG always tweaks their drivers, so they might sound a touch better).

If that sound doesn't work for you, then the closed-back Denon AHD-7000's may be for you. Sennheiser, Audeze, and Stax are all good products as well.

Inna:
I agree with your assessment of Grado. I was comparing $80 to around $400. Not exactly apple to apple. Many consider / considered the SR60 to be the best buy in headphones, which is why I bought them.