Since this thread has turned into a Hydor canister review thread I thought I would share my experiences as well.
I bought a Hydor Professional canister a couple of years ago for a small tank I wanted a quieter alternative to an HOB since it was a couple feet from my sitting position. As soon as a I took it out of the box I was a little concerned about how cheap it felt. I had used canisters from many other manufacturers and I had never felt one so insubstantial. When I was installing the output, the plastic cracked. Keep in mind, I am not a heavy handed person and I was applying very little pressure.
They used obvious sub-par quality plastic components. When you read the reviews, look at how many of the reviewers had the canisters get broken in shipping. While shipping damage happens, it shouldn't cause broken canisters as a common occurrence.
Given the risks involved with the nature of canister filters, it is usually not the place I try to save money. However, if I did want to buy a canister on a budget, I think there are better alternatives for similar money.