The Toyota 2ZZ motor in the lotus uses both. The small lobe has a roller the large lobe (or second cam) uses slipper plates. The stock setup in most Toyota applications the second cam does not engage till around 6500 or 7500 RPN. Louts stock is 6500 my tune like most others it engages at 4500 depending on throttle position and load. My tune keeps it engaged so it does not go back and forth between shifts. Oddly enough the guys that track their cars have less can wipe the those that only street their cars. Makes me wonder if part of the damage happens at engagement. Here is a picture of my cams. Also if i can find it there is a cool video of how it works if I can find it.