Well, I've never seen nor worn the Koala product, so can't comment on it.
Both Capezio and MStevens dancebelts do an excellent job of doing what dancebelts do. They get your goods out of the way, keep everything supported and provide a smooth, clean line under your tights. If you wear them right (up) they really are not uncomfortable once you get used to them.
If you want to show off your package, wear whatever works, but one of the primary functions of a dancebelt is to smooth you out, which means a controlling tightness. These are not boxers we're talking about!
MStevens dancebelts are at least one size smaller than "normal". They advertise their SMALL is for 26 to 28" waist. Does any adult actually have one that size? Capezio is normally sized and whatever size underwear you buy ought to work.
Hope this helps. Dr. Dancebelt is always available to answer legitimate questions regarding male dancewear.[/i]