In my believe praying to Statues just has no effect and therefore it isnt good for us. I dont want to hurt your feelings, just saying what I understand from my monotheistic religion.
Maybe there are some Gods that want you to pray to them in front of a statue. I have no knowledge about that. Seems reasonable to pray to them, but
these being can have 2 forms:
1. created:
If it is created, it doesnt mean that it cant help you, but it implies that there is a creator of that being that is stronger. If we go up in the ladder of creation, we come to the creator who has created existence itself. This one therefore has the most power. So I find it better to pray to the most mighty God who is not created.
2. Uncreated unborn God
To pray to the almighty creator should have the most effect, but statues are not needed to reach him because of his might and they even hinder you from reaching him. Because when you pray to an image, even in your head, how can you say that you pray to the one who doesnt have an image, he who created all the images?