I doubt most people who are into the myth of BBC are disappointed. If one has bought into the "concept" of BBC, then that person also likely is not shy about asking to see or feel the "goods", as part of play in getting comfortable with one another. That is usually done before bringing someone home. (Picture it. You meet someone in a bar. Have a few drinks. Both retire to the restroom to take a piss and get a look or feel.) I doubt very few people bring someone home who isn't up to the standard of what they are looking for these days, unless they are drunk or it's last call; you haven't found what you are looking for; and standards have to be lowered, lol.
If you bring someone home without sizing them up first, you deserve to be disappointed. There isn't a dating site, or app, in this day and age, that doesn't ask for cock size as a vital / required statistic. See how much interest you generate by not putting a number there for cock size (if a Top)…..Even if you didn't meet online, ie. you literally met in person by chance that night, I don't think any top would be surprised by your asking his cock size. It's simply a standard, given question these days, and one is expected to not only answer but also confirm his answer.
Now, I am not saying that all black men are hung (we aren't) but with the way dating, hooking up, or meeting happens today - there is very little room for surprise, unless you are unusually shy or passive. Most tops have that cock size field filled with a number, and we know we will be held accountable to it. Nowadays that accountability usually comes long before we ever go home with someone to have sex.
Hence, the large number of cock pictures with rulers, tape measures, or objects of recognizable size so as to give a relative size comparison. Again, if you are waiting until you get him alone at whatever place you have decided to "do the deed", and you are JUST getting to the "confirmation" step, you deserve to be surprised. Most tops these days are used to having to confirm way earlier... so as to avoid surprises and wasting everyone's time.
I do the same with my bottoms. I have a "finger check" test. If two of my fingers has you asking me to go slower, and three has you pulling away from me, you are not ready to ride this ride. But if three of my fingers has you moaning and begging for the last one, then you deserve front row center seats to this show!