I bought 6 syringes earlier this year, and injected 20 jars. One showed growth (but it may honestly been mold). It's been months, and they're still just plain grain jars.
Like other people, I wish I'd checked these guys out a little more before sending them $40 cash... service was okay (syringes arrived quick), but I think they're only water or diluted so much that they aren't feasible.
A few years ago I'd bought 3 syringes, and one of those grew in one jar.
If you want them for growing, stay away. Out of 9 syringes I've bought from them, only one (possibly two) has had viable spores (and even those only grew in one out of multiple jars... so even with "viable spores" you may end up getting just 1/10 jars to grow).
This company looks great cause they're cheap. DON'T BE FOOLED. Buy more expensive from a different site and KNOW you are getting quality.