That really depend on each individual.
If you have the budget then get both lines. 1/48 for the sizes but incomplete schemes. 1/60 for the complete schemes and better proportion, articulation, and features you don't have in 1/48.
If you don't, then stick with one line if the toy scale does affect you. Apparently 1/60 V2 is the best line I have ever devoted to because I like the vf-1 design so much and I want to have all schemes in one scale.
by the way, I don't even have any 1/48.