I built a Munty frame out of angle iron 10 or more years ago, so it's still there!
Before that I used the traditional inverted 'V' arrangement, which for me has two disadvantages - even in my fairly sheltered garden it needed guy ropes to stop it blowing over when fully laden, and the plants got very congested and the beans hard to spot towards where the canes meet.
"Wigwams' are more stable but the congestion problem was even worse.
A modification of the inverted ''V' is to cross the canes nearer the middle than the top (so more of an 'X' formation) - this avoids the congestion issue and ensures many of the beans are hanging down and easier to pick (a la 'Munty'.)
It's a reasonably stable arrangement, but it does take up more space, and you do require strong canes as they are of course partially unsupported, although I only had the occasional breakage using standard 8' bamboo canes (I chose them individually and with great care!)