Yes, most paper roll cores are 5.5" circumference on the outside.
"The average circumference between 4.67" and 4.97". Both depending on how you interpret the data."
Mr. Average - The true story about penis size, from a site that isn't trying to sell you anything.
I've always interpreted that as the 4.67", not out of optimism but just as the most reasonable point to take based on those data. The study quoted there is the Lifestyles one, where they just went and gathered volunteers to have their dicks measured. It's reasonable to assume that the smaller guys wouldn't volunteer, which would heavily skew the average but not affect the median nearly as much (they have about 300 in the study, so it's a good number of people for a body size study) which is the 4.67" measurement.
Interestingly, about 18% of men are under 4.25" girth, which people on this board think is extraordinarily skinny but is actually pretty normal. That percentage could be much higher too if more skinny-dicked guys would volunteer, and probably accounts for the much smaller girth measured in studies that didn't take volunteers. Only 8% of guys are >5.5" (too big for the tube), and that percentage would be less if they measured more little guys too.
The toilet paper tube test is also a good way to size condoms for yourself. The larger sized condoms are good for people who just barely fit and up.
In terms of preference, at least among women, I think you'll find it's a little big for some, perfect for many, and there are very few who would think it's too small.
thebetty here thinks it's too much for her:
"Toilet paper tube test**??" in Ask a Girl Threads - Webdate.com
If you check sex toy shops, which can be made to any size so give probably the best indication you can hope for of where preferences are distributed, the large majority sold are at 4.75" girth, which is spot-on average. There are plenty of slim ones (4" and less) that get sold to smaller girls and for anal (I feel no sympathy for any skinny-dicked guy who gets regular anal from his girl, lucky SOB) and the 'large' sized ones are usually 5.25-5.5 around. You'll find a few on the high end (6") and the majority of the comments are just people saying they're too big; a lot of those are gag-gifts or are really mushy so their measured girth is different from the actual stretch. Still, the ones who like the super-thick ones tend to _REALLY_ like them, so like everything it's a matter of taste.