The Bullfrog turnouts themselves were easy to build thanks largely to a very good tutorial video made available on Youtube by Fast Tracks.
The Control Rod assembly however, was not easy to install. I spent quite a long time installing all eight of the machines and control rods mostly because the instructions provided with the control rods were pretty poor and they do require careful measuring and cutting to ensure that everything fits and works properly. In addition, the little laser cut wood tool provided to help screw the control rods onto the metal connector that attaches to the switch machine stripped every single time. This left me having to slowly and awkwardly twist the rods onto the machine with a pair of pliers while crouched under the layout table.
If I could suggest one thing to the fine folks at Fast Tracks, it would be to please put out a tutorial video showing how to properly install the control rods. I feel this would have likely eliminated any problem I had during the install process. Frankly, looking back on the experience, I'm not sure I installed them correctly, yet I can't think of what I did wrong and why the installation took so much time and effort.
When all is said and done, I still highly recommend the Bullfrog Manual Switch Machine system. The quality is very good, the price is even better, and they seem to perform flawlessly once installed.