Do big dicks cum more? Size of the flesh has nothing to do with the size of the load that comes out of it.
If you are turned on by big cocks then, yes, they are more fun to suck, stroke, be fucked by, etc.
But asking "what's it like" for others is tough for anyone to relate to, because what each person gets out of sex is different and unique to that person.
I suggest, if you really want to know, is to go and find a partner with a nice big cock and have at it! Have fun and experience it for yourself!
For me, I am extremely envious of big, thick cocks! Especially girthy ones! Visually they excite me, in person I am in awe of them. To feel the size, weight and heft of a big cock gets me very aroused! It feels so cool to handle that size compared to my own. And, speaking of comparing... I love to put my dick side by side and see the contrast.
Yes...for me, bigger is better in every way!