Summary: I use this head for several cameras of different weights. Must change spring for different cameras. Reviewer who said locks don't work needs to read manual. The pan and tilt locks can be re-adjusted with an allen wrench (included) to be tight again. Excellent drag and movement. Outstanding fluid head for cameras in its weight range. Reasonably lightweight and is good for travel. Excellent match with a Gitzo Series 3 Systematic Tripod (with the 75mm bowl).
Summary: Loved the ability to dial in the exact camera balance with the various springs. Had to have it refurbished one year into ownership because the fluid head developed a leak when exposed to extreme cold temperatures. For weeks it oozed black goo until it was rendered useless and I took it in. After 6 years of ownership the pan and tilt brakes have ceased to work.
Summary: I finally took the plunge and bought this head. It's pricy but now I wish I had done it years ago. I made the step to HD which shows every movement flaw in your pans and tilts. My bogen 503 had some jerky starts and stops plus it would move backwards a touch after stopping a pan. All that is history now. The camera is a breeze to balance after installing the proper spring ( go with the lighter one that your camera weight suggests.
Summary: Good choice for globe travel work. Easy to use with 1380 packs nice in DOMKE FX1 bag for take on flights with HVRV1U and extras, NO drifting or floating. Easy to clean. Good work horse. Expertise: IATSE#600, NPPA, 17 years shooting Problems Encountered: Easy to loose 1/4 20 screw, also you need to move the lock down nut for DVCAM and HD systems.