What is More impressive: 8x5.5 or 7.5x6 (real inches)

Girth always wins.

your sex partner wouldnt notice the extra half inch on length, but will definitely notice the extra 3/4" girth, I'm near 6 girth and always get comments from girls and guys. Thats about 1.5" thicker than average.
 
in this case, both. these two are too close in measurements. it's like comparing a huracan to a r8. they're both pretty much the same but have their own encampments of people whom prefer one over the other.

now if we compare huracan to brz then it's a no brainer.
 
When it comes to girth even a quarter of an inch makes a big difference. Women say girth is more important than length and my girth has been appealing to many women. I have met women for sex just because they have seen my photos. One practically opened the conversation with, "I see you have magnificent girth." I met her at her apartment and my cock was inside her for almost three hours straight. I think there's your answer.
 
7.5 x 6 would be more impressive to me. I love GIRTH! And i think the overall volume is bigger than the 8 x 5.5 dick.

Thicker looks more powerful and strong, and the feeling of holding and stroking a thick cock is incredibly satisfying. And having been fucked by one that size this past weekend was amazing as well... girth puts good pressure on my prostate.
 
Depends on what for.

I'm 7.5x6.25. I get a lot of attention due to my thickness. The husband is 8x5.5. He gets MORE attention for his overall size, even though I'm bigger by volume. I know he prefers my thickness over length. For me - both (8x5.25 or 7.25x6) are awesome I wouldn't be able to choose one over the other.