That looks like a great bench, I don't like the fact the part you'll be tying on will have to be loose to move back in place when not tying, I hate anything that moves
when I'm tying, I tye on one of these, I own two of them and they are great, one I've been tying on at the shop for over 15 years, and for 5 or 6 years
before that I tied in the lodge upstairs(R.R. Lodge) when I was living there, great items, and they are rock steady, make one like this and it should last
a couple of lifetimes
http://www.flytyingfurniture.com/Catalog.html#TVtyr