Minecraft: Silverfish Block Builder

After watching Etho setting up the silverfish xp storage system I decided to have a go at a fix for the jamming. I've been playing around with this for a couple of days and have since seen Etho's update and JL2579's version (panda's?).

I realized all I needed to do was create a bottleneck that only let one silverfish through at a time but fast enough to keep up with spawn rates and after hours of testing I consider this design a success. : )