I use a Sachtler Caddy and Vinten Vision 100 for my daily work with the Vinten being able to go for heavier loads. I use a Vision 6 for my wildlife work and have no complaints about it. The counterbalance system of Vinten really wins and trashes the Caddy's 4 step. IMHO, you may want to consider a Vinten though if the camera you are using is really going to lightweight, then the Perfect Balance system wun work.
From what I have read, the smaller Sachtlers are just not worth the buck.