Rabbotai,

There are groups that are producing tcheilet today. First there are the Radziner Chasidim who are using the cuttlefish to produce tcheilet based on the Radziner Rebbe's research of 100 years or so ago. There is evidence that an Italian chemist misled the rebbe by adding iron filings to the cuttlefish dye. Then there is the modern tcheilet produced by amutat ptil tekhelet http://www.tekhelet.com/index.html in Efrat and Kfar Adumim who use a Mediteranean murex snail. A lot of research was done by Chief Rabbi Herzog on the issue. The amutat ptil techeliet has some very convincing research that their tekhelet is the authentic one. An article on it (disagreeing) appeared in the Journal of Halacha. Growing numbers of people are using the amutat brand of tekhelet and there are various views Rambam, Raavad etc. of how to make the tzitzit and tie the knots.

The question is whether there's any down side to using the amutat tekhelet. Could it possibly be worse than using all white like most people do.

B'kavod,

Sam Kosofsky