Should I go with higher magnification or lower magnification?

This is a very personal choice and will vary by each user depending on their needs and uses.

ADVANTAGES
Low magnification: larger Field of View (FOV), larger exit pupil (more light to the eye), easier to hold steady.
High magnification: more detail in distant subjects, objects will appear closer

DISADVANTAGES
Low magnification: less detail in distant subjects, objects will not appear as close.
High magnification
smaller Field of View (FOV), smaller exit pupil (less light to the eye), can be difficult to hold steady (hand shake will be magnified and more apparent).