I am a Zero1 user currently! It is definitely very economical, given that I was one of the first few users, so my plan is at $19.90 per month. Other than one serious outage for half a day a few months back, so far the reception is pretty good. I could not make calls or receive calls or receive any data that half day though, so that’s one thing to take into account. There is also no data roaming available, so if you need to receive sms to activate your credit card overseas, not possible: do that before you get overseas! Other than those mentioned, I have been using since inception and still going strong!