I plan large panels with a live edge and large lumber that is too wide for my planer. This attachment works great and is probably the most economical to use in the end. Inserts are inexpensive and easy to swap out, so you're always ready to go. No more sending in resharpening bits every time you need to flatten a piece of wood! Insoles also last a long time. We have a lot of minerals in the wood here and the blades/bits don't seem to last as long as they could, but the carbide inserts work great. I flattened 8 large slabs on both sides before moving them! Don't try to take too much and don't try to go too fast. Also, be careful not to over-tighten the inserts. I'm a bit picky when it comes to what appears to be an expensive instrument. Buy with confidence!