I have the Heartland inner cam bearing tool, and used it a few times with no problems ... There was only basic instructions and not much on the internet... As there has been some posts regarding what is  a reasonably priced tool for the DIY when installing new cams etc,, the Heartland tool comes up .. 
The video I have posted, is the only video I have seen showing how it works etc ..... It is a bit different than most instruction videos, (As you will soon find out).... But the guy nails it , with the ease that  the the DIY can remove and install inner cam bearings with a reasonably prices tool .....

One thing he does, that is different in the basic instruction , is when performing the removal of bearings, (3.30 minute)....  he screws the collet through the bearing ... The instructions say to Push the collet through the bearing, and you will hear a click ....

I found that the end of the collet, (the end that goes through the bearing), needed to be compressed a small amount for ease of going through bearing, whether you screw, or push the collet through the bearing ....  Personally, if the end of the collet is compressed , screwing it slowly through the bearing, (as he does), seems a better way than pushing, and or giving the collet a tap with a rubber hammer, as it say in the instructions .....
Anyway , those of you that are thinking of a DIY cam install , and are in need of a inner cam bearing tool , hope this is of some interest ....
If not ,, the video should give you a giggle ......