I have got these 2 times, I think a different brand (package shown below), each package had 4-5 bulbs, 3 different types. I did buy at petco or petsmart, I don't remember which. I really really wanted the lily one to sprout, but both times they were duds. The first batch, only the onion plant sprouted. It only had one long "leaf", which ended up breaking and it never grew more.
On the second batch, the aponogeton only sprouted, and this was a pretty amazing one. Once it sprouted, the flower stem parts grew at the rate of over an inch per hour when I moved it out of my smaller tank into the 10 gallon. The leaves have also grown very fast, far more rapid than any other plant I have had.
Definitely not a plant for anything smaller than a 10 gallon. I have it kinda buried in the back of my tank, so pics are hard to get, but I tried. This is all growth in about 2 weeks time. The flower stalks are over 2 feet total, draping across the surface, and the leaves are 6-8 inches long from the base. It's sprouting a new leaf pretty much daily.
I think if nothing has sprouted from the bulbs within 2 weeks, they probably won't. But it doesn't hurt to keep trying to encourage them in a sunny spot til they start to mold. The second batch I added flourish comprehensive to the water, but I don't think it mattered. It's hit and miss. Either it's a good live bulb or it's a dud. Worth it? yeah, I think so. You might just have to try another batch. It's fun somehow seeing one sucessfuly grow.
the surface part:
Sorry for the not so great pics. I just thought it'd be good to try and show the single plant I got out of 8 or 9 bulbs.
I'll probably keep getting the bulbs now and then hoping to get a hit on the waterlily. They're cheap, so what the heck :)