Started getting technical issues already! Almost every time I boot up my PC and FS I loose audio on one of the "decks" on the scratch amp. A bit of fiddling about gets it working again - and then it's stable, but I reckon it could be stressfull in a live environment when your setting up and about to play! It's not good to have doubts in the back of your mind the whole time. Especially when it's so good when it is working that you've already changed your method of mixing based on it!!
The NI forum basically says that the scratch amp on versions 1.x of final scratch suffers some USB issues and windows doesn't configure one of the ports on the amp properly.
A firmware update is required but you have to make and then solder an eeprom chip reprogrammer on to the scratch amp circuit board and then plug this into the parallel port on a PC and let some software reprogram the chip - ****in 'ell!!!!! All that effort to get the code on a chip changed from 0x0100 to 0x0101!
...or you can get the unit replaced if you bought it through an authorised dealer and is under one year old (that rules me out then).
...or you can go for version 2 which has a new scratch amp and uses a firewire port.
So it's something to consider when buying FS........if it's version 1.x it could well have this firmware/USB problem. Luckily my old man is a bit of an electronics wizard and so between us we should be able to get the thing reprogammed (there's a very comprehensive guide to the process on the NI forum).