Side-by-Side Strollers
Side-by-sides are good because the babies have equal access. They are generally lightweight and easy to fold.Tandem (Front/Back) Strollers
Many people feel that they are easier to manuever in tight spaces. They're cheaper and there are more options. Some models allow you to snap in car seats. You can also use them with children of different ages.Where it Stands
You may want both. You may want to wait and see what your babies prefer.
