another Arca-Swiss quick release standard professional head company.
Most of us have 'small' tripods by professional standards, supporting lenses up to 300mm
This is a small head to go with it.
From the manufacturer:
# Weighs less than 1 lb (.45kg) with quick release clamp.
# Easily holds over 25 lbs (11.4kg) at any angle.
What makes Kirk, Arca, R.R.S., etc heads better than Manfrotto, Gitzo, Velbon, Slik?
from my very limited experience, and reviews on the net, I found that professional heads are much smoother in their operation, and mostly eliminate any creep that happens when tightening the head. Another bonus is that all the pro-heads have tension adjustment knobs. These allow you to adjust and readjust the composition without tightening any knobs. On Manfrotto etc you only get these features on larger and much heavier heads, which do not fit on small tripods properly.
The Acratech GV2 Ballhead is indeed very light, yet it is made of solid aluminium and feels very secure and steady. The advantage of Acratech is the dry ball design, making it easy to clean and also meaning that you don't get any resistance or sticking when trying to move the ball. They are a perfect companion to any carbon tripod.
They also make a strangely shaped ultimate ball head, but I think that one would take some getting used to, it looks like that your camera could flop over. The extra range of motion may be good for macro shots though.
As for the quick release plate, they are thinner than Manfrotto, etc ones. I think this is true of all Arca-Swiss standard plates as they are custom fit for your camera.
So why would you spend $xxx on this head instead of a $100 Manfrotto?
Well, I guess it's the same as your non-photographer friend asking why you bought your $300 Manfrotto tripod that weighs 2kg when they have that $30 no brand tripod that weighs less than 500g. I don't know whether it is just all the stores I've been to, but none of the heads I tried were completely smooth. Also, now that I have used it, I would say that tension adjustment is a must. Once you've used it, you can't go back.
I would say it's definitely worth saving up for, if you do serious macro and tele-photo or sport shots, where you would need to fast set up and smooth action. And maybe our currency will go up a bit by that time too!