Kristina from MN wrote (June 15, 2015):

I really like the ease of collecting the specimen, but they aren't made to collect very much blood. The size of the container is misleading as you feel like you should be able to fill it about half to two-thirds full, but if you follow the instructions and fill it correctly, there isn't much specimen to work with. Also, if you get any bubbles in the straw during collection, it's hard to get it going again.