I was going to USA so after lot of research and hesitation, decided to buy roam1 sim in Bangalore. I placed an order and it was delivered within a day by their sales person.
Once I reach USA, I inserted sim in phone and it worked after some time. I pinged them on whatsup and they usually response in 10-15 mins. They uses Lyca sim in USA.
It worked smooth in SFO, LAS, and Chicago. Data was good.
Their plan is cheaper than other similar operators with same quality.
Just go for it.
One more interesting thing, the sim worked in India once I am back and I can dial number till the validity of the sim.