This pencil sharpener sharpened at least 150 pencils from a classroom pack of dull colored pencils. It still works great. It has not gotten gummed up and, while it did get warm, it did not overheat or stop. I only had to stop to empty the shavings.
I did the sharpening myself, so I cannot say whether it will withstand a classroom full of students.
I wish the shavings compartment were bigger and easier to empty. It seems like it could be sturdier.
I highly recommend this product since I haven't found anything better.