I used a set on my blade for a long time, they are really good levers. I got them off eBay from "2 wheels" came in a tie string bag and everything so you know they are quality
I remember at the time there was a lot of naysayers (IIRC led by a group of GSXR forum guys) saying they can cause crashes. This was due to them being incorrectly fitted causing them to apply a gentle pressure on the brakes, boiling the oil and causing a front end lock.
There was also a metalurgist forum member on a .....forum... that did a test on a few sets people sent him and he found that while they were not as strong as the real Pazzo's they were stronger than the OEM levers. The link will be out there still I imagine. They had some really interesting pics of how they are made, Pazzos being machined from a billet and the chinese ones being made from a shaped extrusion, the levers are sliced like bread then finished.
Actually, here is the image.
You can see from the shape they have two end blobs, one for the short versions and one for the full length