DO NOT BUY A YOGGIE, my work mate bought one about 3 months ago and he has had nothing but problems with it.
1. Yoggie keeps blocking ports he has forwarded to open
2. Yoggie themselfs update the firmware whenever they like and have messed it up 3 times in a row because of crap firmware upgrades
3. It only scans 10mb files anything bigger isn't scanned (pointless)
Its a terrible piece of kit and I have been round trying to fix it about 6 times, he has now asked for a refund from yoggie who are going to do so.