I was planning on waiting to buy this for Halloween for my 6 year-old son, but decided to purchase it as a special gift early.  I'm so glad he did.  Ever since the costume arrived, my son has been dressing up as Batman daily.  It's a very well made costume, and has withstood his constant putting it on and taking it off.  It is easy for him to get on himself...with a long opening in the back that has velcro.  The cape also closes with velcro, which is nice as it's less of a chocking hazard.  The mask is well made, a sort of rubbery plastic, and is comfortable for him (and his brother and sister) to wear.  It has velcro straps as well.  I worried that the medium might be too long for him, but it is just right.  He's 4'0" tall.

Really well-made costume that will last beyond Halloween and is great for dress up and role-playing.

Highly recommend it for any Batman fan!  Now I need to find a Robin for my other son.