Girls love the girth, and every pussy is tight. This means sex is always fantastic, but you cant skimp on the foreplay or lube. On the plus side, the girls ive been with say that being really filled up helps them get off more frequently.
Girth makes a cock look really impressive. I love how my cock looks and im only average length (under 6"), being a bit over 6" around adds some illusion to the size. I've had comments from girls (and guys) that i look more like 7" or 8" long. Girls invariably like seeing it, and everyone gets turned on.
I've never had a blow job. well not successfully anyway. Girl gets sore jaws, i get teeth scrapping my cock. This is not pleasant for anyone. I suspect that anal would be limited as well (im not into anal so ive no idea).
buying condoms can be a nightmare. I've found one shop in my town that sells anything remotely wide enough for me. It's a local sex shop, which is a bit awkward. I've run into people i know and had 'oh hi... pause... yeah um im not a nasty lecher really' conversations: not fun. telling someone that you are buying extra large condoms and not porn doesnt make it any easier
Despite the disadvantages, i wouldnt trade my girth for length any day!