Separate names with a comma.
I've been using it for over 8 months. It's perfectly safe.
You don't have to upload any Pokemon in particular, you can catch a random Pokemon, upload it, and check your SID with it. A trainer's SID is stored on every Pokemon he or she catches.
Also, when you upload Pokemon to Pokecheck, they never actually leave the game cartridge. You attempt to upload the Pokemon and you get an error code. In the meantime, Pokecheck will have successfully copied the Pokemon's stats and you'll have a full view of it on the site.
Hi, if you're trying to find your SID, try using this website. You can upload a Pokemon and check everything from the OT's ID/SID, IVs, and EVs.
Hi, I have a legit Jirachi and Mew but they don't have perfect IV's. Those were obtained before I learned to RNG abuse. I have a Manaphy for trade that is RNG abused with flawless IV's. Let me know if you're interested and what you can offer.