The Losing Control is one of if not my favorite "real world" card control. It is hard to go into detail on what it looks like, but it is extremely fair. So let's see..
Is it worth $25?
This is mainly personal preferance. To me: Yes. I have gotten so much use out of this control that it has in effect "paid for itself." The CD is not the highest quality in the world, but it is a fairly entertaining production teaching a great move as well as many variations.
Is it practical?
Again, YES. This is the most practical card control I have ever used. It is all in the hands (for the original control), is clean as can be for the most part, and works in various situations. It is a control that you are BOUND to use.
How difficult is this?
Assuming you are proficient with a pack of cards, the mechanics of the control are quite simple. The motions themselves are not difficult. However, finding the most natural beat and style for yourself can be a bit of work, as well as working up the guts to do it. It is a bit bold, but after you perform it the first time, you will realize that if done correctly, no one will even suspect any moves (which makes for perfect magic)
What seperates it from the rest of the crowd?
I think the major difference is the natural look, flow, and feel of the control. The covering action is something that makes sense, rather than a bunch of extra fiddiling or cutting the pack. Also the fact that technically it is not difficult is a bonus. However, be wary as when you first watch it on video, you may not be as impressed as you should be. This is something to be done live.
Anyways, if you want a practical move, take a plunge and buy it. It has served me well since I purchased it, and only continues to sustain my opinion of Lee's products.
Hope this helps!
J.