The more you pay the better it's going to be. For the companies which are cheap with unlimited everything for like $2-$4 aren't going to be very good because they will be overusing the server and cramming it with all their clients. Whereas if you went with someone who does that for $8-$10 a month they might have a better server and they might have paid for better security on their services.
It's like anything in this world, you get what you pay for. I would personally save some more money up and go for the more dear companies. I have had experience of this, when i first started i went for the cheap companies and i would have to keep changing service every month because the companies either closed because they weren't making any money or they were down because someone hacked them.
It's your choice, but listen to what everyone is saying before you make your decision