I have a didymos and a storch leo (probably the one you are talking about) and they are SO SO wonderful! Get one, you wont regret it! But you can buy on the babywearing down under google group and it will probably be cheaper for you.
I have a Moby Wrap which I absolutely adore but have recently started "making" them for friends. The difference is that I bought a 12m roll of fabric on sale for $15 which will make at least six wrap carriers & a few slings compared with $150 ish for the Moby.
The recommendations are:
* 4.5m length (but you can cut it shorter if you're small)
* 50cm width (usually the fabric you buy will be 1.5m width so you cut it in thirds & have three )
* jersey is recommended (like t-shirt material), when it's cut it curls a little & then you don't have to edge it
* if you get jersey, make sure it stretches only one way
* woven cotton materials are also ok, but you have the edge them with an overlocker or hem
* buy your fabric in one length, sewing two pieces gives you a weight bearing seam
* it's recommended to have fabric that doesn't have a "wrong" side, but I have used a gorgeous striped fabric with a wrong side & you son't notice it
* try to get 100% cotton fabrics because they breath better.
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