I've used the biscut since I started bow hunting so I can't compare it to anything, but it works for me. I started with feather fletchings and it was kinda hard on them. I switched to vanes and noticed the wavyness that Cornfed mentioned but I didn't realize that came from the biscut. I also shoot blazers through it and I have noticed the blazers aren't wavy, but they appear to be bent over some at the top.
One other thing from a long time ago in another thread we discussed helical offset and the biscut. In my opinion, which isn't worth much, a straight fletching will get through the biscut faster than a helical fletching. The straight vanes only have to make one channel through the bristles as wide as the vane but a helical offset the whole vane comes in contact wth the bristles. Think of it as a clock with the cock vane at 12:00, the straight vane will all go throught the biscut at the 12:00 position the helical vane will contact the bristels from the 12:00 to the 1:00 to 3:00 depending on the degree of offset. I don't know if it really makes a big difference or not, but it is something to think about.
Another thing I learned the hard way, on the original biscut the bristles were the same all the way around so I didn't pay any attention to cock feather orientation. When I had a new style biscut put on I was having some very eradic arrow flights. Once in a while one would just go off on a path of its own. Then I figured out there are stiffer bristles (even different colored, duh)at the bottom and a vane would hit that and screw up the flight. So be sure none of your vanes line up with the bottom stiffer bristles.
The 'Bonker