I have a family in my daycare that are sharing custody every other week. Wednesdays they have a visitation dinner. In my experience it is just too much for the children to handle. They don't seem to have a feeling of real belonging when moved around so much. Your situation may be much different but from what I can see with your child's age he needs a stable enviroment.
Hi... I don't mean to sound harsh in what I am posting, just realistic. Please consider the effect on your child of having two sets of households, two sets of rules , and the reality of having to "move" every week, back and forth, back and forth. It may be easier and more convenient for you and your ex, but I think it could instill a real feeling of rootlessness in your child. Wouldn't it be much better for him to have his very own "turf", especailly at such a young age? Just a thought. You seem to want the best for your child , so pelase at least consuder this.
There is no way to generalize about such things, except to say that, in most situations, the sort of custody arrangement you are contemplating tends to be fine. The key ingredient to post-divorce situations is the nature of the post-divorce relationship between the parents. If parents can put aside differences and acrimony and work together in a cooperative spirit in relation to parenting issues, children form families of divorce can do quite well. If the parents engage in conflict, children have a much harder time.