The only real issue then is to decide whether a SIM only contract is a better deal than a PAYG contract. It all depends on what happens whether you go over the data limit what the cost is. Sometimes all you can eat data on contracts can act as a decent safety net, even if it is slightly cheaper to go for a PAYG deal. That extra payment is like insurance against a big bill. In the end only you can decide, though would you be happy to be tied down for another year?