So I got a phone off ebay since my old one is acting up, it's a very basic phone but that's all I need. The dude also gave me a pay as you go style O2 sim that says I can get either 300txts or 100mins a month, just as long as I top up a tenner a month. Is this for real? I mean, 300txts or 100mins for £10 sounds quite good, is there a catch on this thing?