Hockey pucks are a hard rubber that does not flex very much before tearing or breaking into chunks.
The risk of the bushing failing is quite a bit higher than with regular rubber bushings. In order to use the hockey pucks, you will need to weld a steel strap arond the perimiter about 3/4" wide. If you don't do this, the bushing will squish when you apply torque to the subframe bolt and it will begin to crack and split from the pressure almost immediately.
In addition, since the hole in the subframe is what...58mm wide and the bolt is 12mm wide? There will be no way to keep the subframe from walking a bit either way
Successful hockeypuck subframe bushing setups are created by welding an 1/8" steel plate over the 58mm holes in the subframe. Then, you drill a 1/2" hole in the middle of the plate for the subframe bolt to go through. This will limit side-to-side subframe movement completely. Installed this way, hockey puck subframe bushings are not only sufficient, but argueably, a performance upgrade.
The downside to this method of securing the subframe to the car is the fact that now, you don't have any angular shock absorbsion. Hit a curb and chances for serious subframe damage are much higher. In addition, this method is probably more dangerous in a crash.
Another way of filling that hole is to cut a piece of delrin or plastic to be 57.5mm in diameter and putting the bolt through that, sandwiching it between the pucks. This limits movement also, but this way, if there is a great angular shock, the delrin can break up and save the subframe