On the new www.ushaidong.org web site, there is an order form for "official" jin gums.

On the form, they have these selections:

Bamboo Cutting
Sword Circle type of sword: Flower Tiger Dragon Gold Dragon
Straw Cutting
Sword Circle type of sword: Eagle

What are the differences in a bamboo cutting jingum vs a straw cutting jingum? What are the differences between the different types of bamboo cutting swords?

Thanks!

Simply put: Bamboo cutting swords (Yuk kakdo, 6 sided blade) are stronger and can be used for bamboo or straw. Straw cutting swords (Sam kakdo, 3 sided blade) have a thinner profile and should only be used for cutting straw. Were you to use a Sam kakdo on bamboo you'd ruin your sword or potentially hurt yourself or someone else.

Why the difference? Most use the Yuk kakdo for practise and training, it's the standard. The Sam kakdo's thiner profile and lighter weight make it better suited for demonstrations or specialized straw cutting. I suspect it's also cheaper.

Of the different bamboo sword types you mentioned I believe the differences are purely cosmetic. Higher end modles having more elaborate decorations (eg: pearl inlay on the scabbard, or dragon etching on the blade). I'm not sure exactly which models include which options.

Yuk kakdo in order of cost, low to high:
Flower
Tiger
Dragon
Gold Dragon
On the models of each I have seen, the blades all look the same as far as physical dimensions and such go, it does seem to be the fittings and accessories that drive the cost.
The sam kakdo, though, is not cheaper. The three sided blade is harder to manufacture successfully, so it's more expensive. I think the price i heard last made it cost the same as a Dragon, though it may be even a little more than that.