Okay I didn't really loose it - I know exactly where it is....
My primary tripod is a Gitzo GT5540LS with a Arca Swiss Cube sitting on top. This has been my rock solid system for several years. The only drawback is it's heavy weighing in at just shy of 10 pounds. Not too bad if I don't have to carry it long distances.
I've been working on getting a good lightweight system for when I'm out beyond a mile. I picked up a Feisol CT-3442 last year just before I made a trip to Utah using it successfully along with a combination of an Acratech leveling base and Really Right Stuff PCL-1 B. Ultra lightweight system weighing in at less than 5 pounds. The drawback is it isn't geared thus slower and less accurate than what I want.
Now however I have a Arca Swiss D4 sitting on top of the Feisol which gives me a total weight of slightly more than what I had previously but 5 pounds less than my Gitzo/Cube. Five-pounds might not seem like a lot however that's almost a full gallon of water which means a heck of a lot.
I'll shortly be hiking in Glacier National Park and will be using the new Feisol/D4 system along with my WRS and I'm looking forward to it.
I've read posts from folks that say the D4 is as good as the Cube and so far with just minor experimentation I agree. The one thing I've seen is that the controls seem to be backwards in that the axis controls are the reverse of the Cube. So far I don't see the D4 as a replacement to the Cube - I do see it as a kickass hiking tool.