I live in the United States and have found *no sources* to provide good test kits with very functional packaging. They come in little bottles with a spout that makes it easy to control the amount of reagent you use.
There are a couple ment to keep you dancing safely.
Marquis is good for mdxx substances.
I'd go marquis mecke simons. Then you really know what your ingesting and can test a number of substances.
Also I believe you save money buying the pack vs. Individual.