"I ordered the bundle from worldsim.com with 1GB when travelling to US. First issue I faced was that I couldn't get internet working on my phone. So I had to spend around 40min in the airport where was the free wi-fi to consult with support in chat so they could enable the data for me and I could start using it.

After using around 500MB the internet stopped working. I had to find wi-fi and contact support (because I couldn't call the support) and they told me that my bundle is over. Ok, I thought maybe it's some mistake, so I ordered another bundle (had to pay more for it somehow, as initial price isn't available when you top-up). And again, after another ~500MB the internet was shut down. Support told me again, that I've used whole 1GB. They told me that's because they count sessions in 1MB increment. I don't know how this works, but buying 500MB from my provider for the same price got me the same results, as my provider counts data correctly and if I buy 500MB, I can use 500MB, not the half.

AVOID this scam company (worldsim.com) if you can. Buying any pre-paid card in US would be cheaper for me in any way, but I didn't know how crappy this company is. Next time I'll use my provider's internet or will look for pre-paid cards in the destination country AND WILL NEVER USE THIS SCAM COMPANY!!!"