Mine are useless. They are super heavy, and on top of that the pulleys are super-super heavy made of iron, steele (or God knows what) 
. Who manufactured these pulleys? Disgruntled engineers? Masochists? Geeeeezzz!!
Got so pissed installing these wheels that I gave up. Never felt so frustrated installing smthng for Esk8. I was going to forget the wheels were already too heavy when I installed them on the trucks. No problem there. But when I unpacked the pulleys I couldn’t believe it they where so heavy! Why?? Who is the maniac who created such a pulley and so heavy?? What’s the purpose? No access to Nylon, Acetal Delrin or any other hard industrial plastic material?
And it was not so much that they were heavy but the fact that they were really well built. The pulley from the manufacturing standpoint is almost perfect. The CNC is flawless, but how come they can produce such a perfect pulley but with such complexity, made of various different metal pieces assembled together with a bunch of bolts? Metal everywhere and bolts like there was no tomorrow! What?? No wonder why the pulley is so heavy 
!
And then when I was trying to install the pulleys on the rear wheels I found the sprockets came with rubber covers on them! I thought that was a nice touch, “they want to protect the sprockets!”. Well, actually the sprockets were so tiny compared with your normal ABEC type sprockets, they look ridiculously disproportionate, and not only that but they are sharp as X-Acto blades. So much that I ended up cutting my fingers with them! 
First pulley went in with no problem, but the second one couldn’t enter the wheel hub “what in h…?” Well, it turned out they sent a pulley with a different sprocket profile for another wheel style, similar to the other pulley but with the sprockets edge profile facing backwards and I couldn’t introduce them on the wheel hub.
End result: a useless heavy rubber wheel set with no working pulleys. The bearings snugly fitted inside the hubs bearing wells, the CNC machining and anodizing finish was perfect, but the wheels are incredibly heavy and the pulleys even heavier; overengineered, made out of various metal parts and lots of bolts. A heavy proposition. I still got them on one corner. The heaviest paper weights you can think of 
.
