We assume that most K series engine owners already have a 50° intake cam gear... so it made total sense to limit the 50° gear rather than ask customers to go through the trouble of finding a 25° TSX gear and have it machined. The process is tedious, you must find a 25° RBB gear and obviously buy it, pay to have it shipped, find a capable machine shop to handle the modification, ship it to them, pay them their fee, and ultimately pay for the return freight. Sounds expensive! Not to mention a total headache and a major inconvenience.
Don't forget to ask yourself what happens when you need more or less cam angle? I guess you'll have to repeat the process.
The TTS VTC Limiter is manufactured from precision ground 52100 Bearing Steel and finished to exacting tolerances (+/- .0001") and then heat treated to a hardness of 60-62 Rockwell C. The limiter works by placing the pin in a specific cavity of the VTC gear, where it is allowed to move freely. Centrifugal force locates the pin in the correct position once the engine is in operation... much like the ride you see at the carnival that spins and pins you up against the wall, where it mechanically limits the amount of movement; regardless of what the ECU is telling the solenoid to do!