This is just right for my son. I'm happy with the purchase, though there were a couple things that I'd have changed (hence not a full 5 stars). The material was a little thinner than I expected (though not as worrisome as some other reviewers felt). I think the sizes DO run a little small. I bought the 2-4 for my 2 1/2 year old son expecting it to be a little baggy on him. It is a perfect fit. If you're looking to buy this for your 4 year old you will probably want to look elsewhere. My only complaint, really, is that there could have been another velcro enclosure or two down the back. The opening was pretty wide (leaving the back bare if he doesn't wear a shirt under it). I had some sticky-back velcro kicking around so I just slapped it on there, so it was an easy fix for me but mildly inconvenient. Overall I am happy with it and my boy is the cutest little Superman you ever did see.