We purchased thermalwear for both our son and daughter for swim lessons at the local YMCA. Excellent quality, excellent fit. This two-piece set, available only for boys (or girls willing to wear skulls), is the far superior option. It fits each part of the body well and doesn't collect lots of water, like the one-piece option. My daughter is frequently seen draining her suit . . . But at least she's warm.

Using this for my 4yr old sons swim class - no more shivering!  It kept him warm and very mobile for the class.  Great product.

my 4 year old uses this is in the pool for lessons.  he is a small 4T and I ordered a 5T with 'growing into it' hopes; it is snug.

It is not overly insulated. I think it helps a little with warmth, but not as much as I was hoping, espcially for the price. He still comes out cold. And I was not thrilled with skulls as the only option for a 4 year old.

On the up side, the zipper is easy and quick to take off once he gets out- I can get that warm towel on him quickly.

Overall, I would say shop around for the price...