Well, just in case...
if they look like THESE, then they are piperazines:
Also, if they taste extremely sour/acidic and fizz/burn a bit on the tongue, then they are definitely piperazines. Now, piperazines can be quite enjoyable for some when they know they are taking piperazines, but they seem to make lots of people sick as well...I am one of those that can enjoy them and tolerate them just fine(as long as I know that's what I am taking, as I did about three hours ago), but they are no substitute for rolling, that's for damn sure.
Now, if they look like THESE:
then they very well could be legit. As I can tell that you don't have a testing kit, lick the back of the pill and get a feel for what it tastes like. If it's extremely bitter and has no citric/acidic taste to it and doesn't burn your tongue, then you have a legit Blue Fuck You. And if it's legit, then REMEMBER that taste. If you can't get a test kit, then lick your pills before you ingest them and if they taste like the taste you remember from a legit pill, then it's quite possibly a legit pill, but remember, if it tastes acidic/citric/sour and burns your tongue, then it's a piper pressie.
It's crazy, these pills were around only a little over a month ago, and a copycat batch has already been made...
Goes to show, the ecstasy scene is lacking the love and respect these days that it once had before all of this bullshit... Bring back the PLUR, DAMN YOU!
Much love,
and I hope this helps,
stonedandrolling89