What's also important is the type of infeed drum. It greatly influences how the fiber is initially processed. All of the Strauch drum carders use a special carding cloth on the small in-feed drum.
The unique Slicker-Licker on the small drum uses very smooth blades instead of conventional pins. Years of use have shown that these blade-like teeth are far superior to the pin style in feeding fiber to the large drum. The very smooth blades tend to pre-align the fiber and make transfer to the large drum more complete with minimal fiber buildup on the small drum and most importantly, no damage to your precious fiber.
Other carders use standard card cloth on BOTH drums -- hence fiber tends to constantly wrap around the infeed drum.