Adjustable Hole Cutter 40-200mm with Cowling for Metal & Wood

I have been using this product for a couple of months now. Originally I was torn whether to spend this much cash on this unit or get the cheaper Klein Tools version in my local hardware store. Truthfully, I am glad I invested the extra cash in this unit.The construction is higher quality with this unit. The variable dimensions are greater with this unit in that it can cut smaller and larger holes than the Klein unit. The debris tray has a better gasket to catch more dust and drywall fragments.It has a set of blades/guide bit that handily and accurately cut tin ceiling tile.The only drawback to this unit is that there are no instructions and no clear labelling of which blades are which. You kind of have to know what you are doing or research online to see the difference between the blades or look at the box picture to see how to assemble it. That little 15 cents of printed paper would really make a difference between a four star and five star review in my opinion. I hope they include instructions and better labeling of the blades in the future.I bought this to drill holes into 18mm MDF to make speaker mount tubes for my van. A handy feature of this is that you can adjust each side separately to cut 2 holes at once which leaves you with a nice donut shape which is good. You have to be very careful when you first start drilling though because when the bit goes through the wood it wants to drop suddenly and the spikes catch and it tries to break your wrists, other than that it's very easy to use. Burnt my drill out after cutting 3 donuts though but I bought a Bosch drill to replace it with and it's cut 10 more since with no issues whatsoever. Just make sure if you buy this you have a good quality drill to pair it with and you'll be fine.Once set up and tightened, it is easy to get going. I am using it to cut holes in 12.5mm plywood, and it gets going fine but seems to lock up just before it finishes the cut. I had to finish off the cut with a small saw, which sort of defeats the purpose of it. I had hoped that it would cut holes, not leave the job unfinished. Regardless, it did help. Perhaps this is error on my part, but I cannot see how. I have yet to try it with the alternate set of blades.A note - even when all the components have been tightened before cutting, they have, on several occasions, become loose during the cut.Really handy but of kit but with just 2 legs it can be hard for larger diameter holes especially when working overhead. Great at containing dust.Good until you catch tin... only any use if you know your only going to be cutting boardNot what I expected