I was always the biggest guy for every girl untik my wife. She had one friend with benefits in college who had an absurdly huge cock. Longer than my longest erections (I get up to 8.5" at best) and only slightly thinner than the maximum pumped girth that I've ever fucked her with (about 6.5-6.75"). So this guy is somewhere in the ballpark of 9.5-10x6.5 - one of the biggest dicks on the planet.
I waver between feelings. Most of the time, I don't care at all. Doesn't enter my thoughts. I know my wife enjoys me more, so I don't think about other men.
On random days, though, I feel jealous that she was more "intimidated" by him than by me, because she is kind of a size queen so I know that she was extremely aroused to find out he had a monster in his pants. I feel jealous that he touched spots inside her that I never can - although, TBH, I am sometimes too long for her depending on the time of the month. And sometimes, I am grateful to him, because I'm happy that my wife had great sex before we met (not only with him, but he was one of them) and I think her taking him is part of why she had no fear taking me early on. The two of us are MUCH bigger than average and way bigger than all the rest she had. And sometimes, I wish I could see pictures or videos of her with him just to know what she was like in those days on an even bigger cock than my already huge cock, out of curiosity more than anything else.