Why don't you try it when a bunch of friends or family are around? Cut it into wedges, and invite everyone to taste?
I like them - the beans are mashed into a thick paste with sugar. The texture is similar to fudge, but less fatty, more mealy.
The only comparable thing I can think of is the inside of some protein bars - there's a little bean flavor, but sweet, dense . . . and that's not really a good comparison.
Serve them with tea - preferably green tea, or even black tea, like Lipton, but unsweetened. The sweet of the bun is complemented by the unsweet tea, and sweet tea would be too sweet.
Enjoy them . . .