Have grandfathered Simple Choice Promo Plan cosidering switching to ONE

i also have been trying to compare old plans with newer ones based on mexico connectivity.  It seems as if the old simple choice plan gives more options than newer plans for mexico.  That is my immediate understanding because on the newer plans it delineates between phone calls and texts [and possibly other data usage] when you are abroad and gets into details regarding where /which country you are in and which country you are calling to.  the older plan i believe give you everything calls and texts both to and abroad and when you are abroad. i am keeping my old plan prepaid because i like the international feature and i dont trust that i would get the same benefits on new phones.  i am worried because i got a new smart phone and i only have 2gb of data but i figure i will just have to be very careful and or use my wifi when i am at home if i go on the phone.