I have the Audio One from Audioparts Inc that auctions here on AudiogoN, I have found it to be the easiest of all to use. It is more money that the stock digital scales, but it is much easier to use since it is never necessary to reset the VTA of my tonearm in order to get an accurate reading. The inexpensive digital scales are just to thick to make the process simple and the A1 solves this problem beautifully.
Has anyone used electronic pocket scales for VTF?
I use pocket scale from http://www.saveonscales.com/pocket.html to set stylus tracking force sucessfully. These scales have 0.1 gram increments which should be good enough for VTF.