[fasteo]

Not what you are asking, but save you some money and get some IKEA DIY stand-up desk. Been using it for about a year.

for example, http://lukethomas.com/100-dollar-ikea-stand-up-desk/

[UnoriginalGuy]

I own that, and trust me when I tell you that even when the legs aren't fully extended (as shown) the thing isn't super-stable.

It is impossible to get all four legs to exactly the same length (even if you use the guide marks). He has it resting against a wall for a reason.

I would recommend it, but it might wobble around a little if you put any weight unevenly on the surface.

[yaj]

I will recommend this DIY standing desk, http://www.ikeahackers.net/2012/05/standing-desk-with-utby-l.... It is simple, cheap and very stable.

I have the desk for a year now and it solved my shoulder and back problems from sitting too long.