I actually prefer them to regular rubber. Better control in my mind. Maybe its just in my mind- but they sure look great and I either like them better or dont feel they are any worse. Just because we have new technology and can make a different material does not mean it impacts the game negatively-
Purists I can understand- i am in some ways a purist-just not a pinball rubber purist! I dont feel they in any way break pinball-YMMV-
Give them a try. If you like it its a cheap upgrade. If you hate it. Its a cheap test and you know you hate it.