I feel it gives me better control over the plug and better feedback. When I can I always use a two pronger, though they are not as versitile as the "L" wrenches. Grab one and see how you like it.
"Reverse the obvious and the truth will present itself." - Carl Jung
My eye sight must be getting worse.
All those tension wrenches look like single bladed to me.
TW-18 just has 2 different sizes(different size on each end).
[URL=http://www.btinternet.com/~the_mouse/mouse/pages/sigs/sigs.htm] [/URL]
^click for sigs^
I find there is often a very different feel when picking a lock with a double pronged wrench. Top and bottom tension seems to allow for better control and better feel. I would use them more often myself, except that they are often awkward to use when picking locks in hand (my preferred form of practice).