I had a couple of wood items that needed minor repair, and remembered that a friend had used this product before to sculpt a missing ear for an antique carousel horse she owned. She recommended it highly, so I purchased some and tried it. It seems to work well, adhering to the wood and bonding to it. I have not yet tried sanding or painting it, but don't expect any problems. Though my use of it is limited, it seems to be superior to wood filler and allows you to actually recreate missing pieces of wood, if you have the ability to do so.
I've used Sculpwood many times and in many applications. Keep in mind that using it REQUIRES gloves! If a project is important to you, then it's wise to use surgical-quality gloves, for tapered fingers. A little goes a long way, so don't "over-mix".
That being said, it's very effective at filling holes, cracks, etc., and for "building out" uneven boards. Let it cure overnight, and the next day, your repair is as hard and permanent as the original wood it's attached to.