Whats your opinion on printing PLA straight on to a very clean sheet of glass?

I tried the Warpinator 5000 on a sheet of glass on my printer, and 1/4 sides stuck firmly in place.

I probably would have had better results if I'd have cleaned it better, but the Warpinator is a tough print!

The PLA on glass technique is usually done with a brim, something I did not use here.

But my favourite part of the glass is that as Ivan said, the parts just come right off the glass when it cools down. I didn't even have to pry it, it was just sitting on the printbed, and I picked it up.