Quoting lolajessup:" I would probably start with one until I knew I wanted to buy more. im just gonna get one or so of each ... [snip!] ... one or so of each kind I am looking into. it said about $17-20 for one depending on what you said about bamboo or ultra soft."
Bamboo is more expensive.The process they use for bamboo makes the diapers/inserts thinner.Bamboo also takes longer to dry and should not be put in the dryer (they are more delicate).
I went with the ultrasoft for the simple fact that they dry faster and the youtube video I watch showed an absorbency test between the two (ultrasoft and bamboo) and ultrasoft held a little more.Not a big difference so the actual cost played a role as well.
Just remember you can always sell the diapers you don't want to put money towards the ones you do want.