I am led to believe that 48 are the cheapest at 10 euros per month for the basic package which gives a certain number of freebies- I think it is 300 mobile minutes, all texts,3gb data and 60 minutes to landlines. They also have roaming. The downside is that you can’t make calls to premium numbers or competition lines . Calls To UK numbers are not included in the ten euros but you can buy extra credit. I think 48 was originally for 18 to 22 year olds bit is now open to all.