GPRS is the data model of 2G mobile networks. so u cannot compare 2G and GPRS since they both are same. EDGE is the enhanced model of GPRS which we used to call 2.5G. when u compare GPRS and EDGE , EDGE is faster. GRPS can go max on 114.4kbps where EDGE is 343kbps on max. (not sure about exact values. check on google)