well - from my perspective ...
my ex husband was very well endowed (9ins approx and slightly on the thicker side - but not thick thick girth) and a lot of the time he hurt me, it wasn't comfortable and it certainly wasn't fun
my ex-boyfriend was what you would call average (i remember being slightly disappointed the first time I held his cock and thought - is this it?) But by god - he knew what to do with it, and every time (and I do mean everytime) it was like a scene from the movies where you could tell they were acting out "best sex ever" - we had that every night - and I miss it - a lot!
But what you have to bear in mind - after I was stitched up after having my daughter, I was literally given a fanny job - as my ex-bf put it "it's hard to believe you're a mother - you're tighter than a 17 year old virgin". They did a good job patching me up. So, I'm not exactly big down there, which is probably why sex with my husband was shit - but awesome after I left him with my exbf.