Description of problem: Accessing my Treo 650 via generic USB and libusb is 3-4x faster then via the visor kernel module and /dev/USB1. On FC5 all the code and pieces are in place for libusb to work except for the fact that pilot-link was not compiled with "--enable-libusb". Please edit the SPEC file and add "--enable-libusb" to the configure parameters. I have done this on my local box and it works great. SUSE 10 is doing this as well. If an errata update for FC5 could be released with this change that would be most excellent!
We will push the stable release of pilot-link-0.11.8 back into fc4/fc5 update because pilot-link-0.12 pre release caused so many critical issues! The stable release still does not support libusb yet. Of course we will enable libusb if we have the stable release pilot-link-0.12 back in next comming FC. Thanks for your report.